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08-07-88/T\SWR02
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
Tape/disk: | Home » CEEFAX disks » telesoftware8.adl |
Filename: | 08-07-88/T\SWR02 |
Read OK: | ✔ |
File size: | 49FA bytes |
Load address: | 0000 |
Exec address: | FFFFFFFF |
Duplicates
There is 1 duplicate copy of this file in the archive:
- CEEFAX disks » telesoftware3.adl » 01_11_87/T\SWR02
- CEEFAX disks » telesoftware8.adl » 08-07-88/T\SWR02
File contents
Mastering Sideways ROM & RAM - Module 02 - Rom headers ------------------------------------------------------ Paged roms and sideways rams can contain languages, utilities or programs and data stored in the RFS. All roms, whatever they contain, must be recognised by the operating system. To be recognised the first dozen or so bytes must use the rom header format shown in figure 2.1. The first 10 bytes of the header from &8000 to &8009 have fixed positions in memory and must conform with the pattern shown but, because the copyright and title strings vary in length and because some of the rest of the header is optional, the header does not have a fixed size. Memory map Memory map of rom of header &BFFF +-----------+ /+-----------------------+ ! ! / !Tube relocation address! ! ! ! !&00 ! ! ! / !Copyright string ! ! ! ! !&00 ! ! ! / !Optional version string! ! Rom code ! ! !&00 ! ! ! / !Rom title string ! &8009- ... ! ! ! !Binary version number ! &8008 +-----------+ / !Copyright offset ! &8007 !Interpreter! ! !Rom type byte ! &8006 +-----------+/ !JMP service ! &8003-&8005 ! Header ! !JMP language ! &8000-&8002 &8000 +-----------+ - - - +-----------------------+ Figure 2.1 The Rom Header ------------------------- The first three bytes of the rom header (&8000-&8002) contain the language entry point or, if the rom is not a language, the three bytes will all be zero. The first byte of the language entry point is a JMP opcode followed by the two byte address of the start of the language coding. A language in the BBC micro can be any machine code program which is completely independant of any other language and can take over the processing of input and the production of output until another language is selected to replace it. As far as the BBC micro is concerned Word processors, spreadsheets and machine code monitors all fall into the same category as the more readily recognised languages Logo, Forth and Pascal. Language roms will not be considered until module 17 and so, for the first part of the course, the rom headers will all have zero in the first three bytes. The next three bytes of the rom header (&8003-&8005) contain the service entry point. All roms, except BASIC, must have a service entry point. The first byte of the service entry point is a JMP opcode followed by the two byte address of an interpreter which must process the service requests made by the MOS. Service requests are made to each rom in turn when, for example, the MOS finds an unrecognised * command or when you type *HELP. The address of the interpreter is usually the first byte after the end of the header, as shown in the rom memory map, but you can assemble the interpreter anywhere you like within the 16k of memory available to the SWR. The design of service request interpreters will form a very important part of this course. The byte at &8006 is the rom type byte you met briefly in module 1. The rom type byte is a flag byte which tells the MOS what the rom is expected to do. Bit 1 of the byte is always set on all roms except BASIC and bits 0, 2 and 3 are always clear. Bit 4 controls the Electron soft key expansions and is always clear on the BBC micro. Bit 5 is set if the rom is a language rom with the language coding assembled to run in a second processor. Bit 5 will be clear in all the examples covered in this course. Bit 6 is set if the rom has a language entry and bit 7 is set if the rom has a service entry. All roms, except BASIC, have bit 7 set. In the examples covered in this course the rom type byte will have one of only two values. Service roms will have &82 stored at &8006 and language roms will have &C2 stored at &8006. &82 = 1000 0010 binary, ie. service entry point and bit 1 set, &C2 = 1100 0010 binary, ie. language and service entry points and bit 1 set. If you use the program READROM (from module 1) to look at some of the roms you have in your computer there are two other values you might find at &8006. BASIC has &60 stored at &8006 because it does not have a service entry point and bit 1 is clear. "Hi" versions of languages (except Hi-BASIC) have &D2 stored at &8006 because they have a tube relocation address as well as language and service entry points. The copyright offset pointer at &8007 is the offset from &8000 to the zero byte preceding the mandatory copyright string. The copyright string must start in the first &FF bytes of the rom image and the copyright offset pointer stores the least significant byte of the address of the zero byte preceding the string. (See figure 2.2) The binary version number at &8008 is ignored by the MOS. It can have any value from &00 to &FF and is used to indicate the version number of the rom. The title string starts at &8009 and must end with a zero byte. The title string is printed out by the MOS on selection of the rom as a language rom. It will also be used as a command name in the simple one-command interpreters used in some of the modules in this course. The version string is optional and, if it is used, it must follow the zero byte at the end of the title string. The version string will not be used in any of the examples in this course. The copyright string is essential because the MOS uses this string to recognise the rom and, if it does not exist, the rom will be ignored by the MOS. The format must always be a zero byte followed by "(C)" and whatever else you want to include and then another zero byte. The minimum copyright string is a zero byte followed by "(C)" and another zero byte. The tube relocation address, if present, is a 4 byte address at which the language part of the rom has been assembled. Tube relocation will not be covered in this course. Writing the source code for the header is much easier that writing about it. The optional version string has been left out of all the example programs. The source code for the header of the program TRACE assembles as shown in figure 2.2. You can see that it is &29 bytes long but it could be shorter if it used the minimum copyright string of "(C)". Figure 2.2 is a BASIC 2 version of TRACE assembled with bit zero of the OPT directive set. 8000 00 EQUB &00 \ No language 8001 00 EQUB &00 \ entry point 8002 00 EQUB &00 8003 4C 2A 80 JMP service \ Service entry point 8006 82 EQUB &82 \ Rom type byte 8007 0E EQUB copyright MOD 256 \ copyright offset 8008 00 EQUB &00 \ Binary version 8009 54 52 41 43 45 EQUS "TRACE" \ Title string 800E .copyright 800E 00 EQUB &00 800F 28 43 29 20 47 6F 72 64 6F 6E 20 48 6F 72 73 69 6E 67 74 6F 6E 20 31 39 38 37 EQUS "(C) Gordon Horsington 1987" 8029 00 EQUB &00 802A .service \ Start of interpreter Figure 2.2 The rom header of TRACE ---------------------------------- When the MOS requests the paged roms to provide a service the highest priority rom, rom &0F, is offered the first opportunity to respond to the request. It is entered at the service entry point with the registers set up as shown in figure 2.3. Register Service call information ---------------------------------------------------------- Accumulator Service type requested X register Number of current rom Y register Any parameter required for the service Figure 2.3 Service call registers. ---------------------------------- If rom &0F is unable to provide the service requested it must exit using RTS with all three registers preserved and the next rom, rom &0E, will be given the same opportunity to provide the service, and so on down to rom &00. If a rom is able to provide the service requested, and does not want any other rom to attempt to provide the same service, the accumulator should be zero on exit. The program TRACE is used to provide a display of the service requests made to the sideways ram bank containing the object code it generates. Chain the program and, when prompted, give a filename for the object code which will be saved on disc or tape before you load it into SWR. It is not necessary to include a quotation mark before and after the filename. After saving the object code, load it into SWR and press the Break key. You will immediately see a display of the service requests sent to the roms when break is pressed. Type *HELP and you will see the help service request. Type *DISC or *ROM or whatever else you think will make service requests to the paged roms and you will soon get to know the service request codes. Do not use TRACE when *SPOOLing or *EXECing files. If you do it will cause the computer to hang up. The service request codes are summerised in figure 2.4. 00 No operation. A higher priority rom has already provided the service requested. 01 Absolute workspace claim. This will be dealt with in module 12. 02 Private workspace claim. Modules 11 and 13. 03 Auto-boot. Modules 19, 23, 24. 04 Unrecognised command. Modules 3, 5, 8, 9, 10, 11, 13, 15, 16, 17, 20, 21, 22, 23, 24. 05 Unrecognised interupt. Module 14. 06 Break. Module 13. 07 Unrecognised Osbyte. Module 6. 08 Unrecognised Osword. Module 7. 09 *HELP. Modules 16, 17, 23, 24. 0A Claim static workspace. Module 12. 0B NMI release. Not covered in this course. 0C NMI claim. Not covered in this course. 0D Rom Filing System initialise. Modules 18, 19, 20, 21, 22, 23, 24. 0E Rom Filing System byte get. Modules 18, 19, 20, 21, 22, 23, 24. 0F Vectors claimed. Not covered in this course. 10 SPOOL/EXEC file closure warning. Not covered in this course. 11 Font implosion/explosion warning. Not covered in this course. 12 Initialise filing system. Not covered in this course. FE Tube system post initialisation. Modules 12, 22 (illegal use). FF Tube system main initialisation. Not covered in this course. Figure 2.4 BBC B Service requests. ---------------------------------- The program TRACE works by intercepting every service request sent to the SWR. Before doing anything else it preserves the A, X and Y registers and the two zero page memory locations used by the print routine by pushing them on the stack (lines 310,370). It then retrieves the service request from the stack and pushes it back onto the top of the stack (lines 380-400) followed by the Y, X and A registers again (lines 420-470). It then selects a yellow foreground colour if Mode 7 is used (lines 480-560) and prints the content of the accumulator, the X and Y registers in hexadecimal (lines 570-680). An explanation of the service request type is then given for the BBC B service requests (lines 690-870). The Master computer uses service requests not available on the BBC B and the content of the registers for these requests is shown but not described. The program exits with all the registers and memory locations restored (lines 880-990). Having the trace active all the time is both distracting and undesirable. You can disable the utility by read protecting the sideways ram bank or by loading some other rom image to replace it. Always press Ctrl+Break after read protecting SWR or reloading a rom image. Although the Master computer uses service requests that are not available on the B series it uses all the B series service requests as well. For this reason all properly written software for the BBC B will also work on the Master but it will not make use of the the extra facilities, such as paged workspace, without responding to the Master specific service requests. 10 REM: TRACE 20 MODE7 30 HIMEM=&3C00 40 DIM save 50 50 diff=&8000-HIMEM 60 address=&70 70 stack=&105 80 mode=&355 90 osasci=&FFE3 100 osnewl=&FFE7 110 oscli=&FFF7 120 FOR pass = 0 TO 2 STEP 2 130 P%=HIMEM 140 [ OPT pass 150 BRK 160 BRK 170 BRK 180 JMP service+diff 190 OPT FNequb(&82) 200 OPT FNequb((copyright+diff) MOD 256) 210 BRK 220 OPT FNequs("TRACE") 230 .copyright 240 BRK 250 OPT FNequs("(C) Gordon Horsington 1987") 260 BRK 270 .service 280 PHA 290 TXA 300 PHA 310 TYA 320 PHA 330 LDA address 340 PHA 350 STX address 360 LDA address+1 370 PHA 380 TSX 390 LDA stack,X 400 PHA 410 STA address+1 420 TYA 430 PHA 440 LDA address 450 PHA 460 LDA address+1 470 PHA 480 LDA mode 490 CMP #&07 500 BNE notmode7 510 LDA #&83 520 BNE space 530 .notmode7 540 LDA #ASC(" ") 550 .space 560 JSR osasci 570 LDA #ASC("A") 580 JSR equals+diff 590 PLA 600 JSR printbyte+diff 610 LDA #ASC("X") 620 JSR equals+diff 630 PLA 640 JSR printbyte+diff 650 LDA #ASC("Y") 660 JSR equals+diff 670 PLA 680 JSR printbyte+diff 690 PLA 700 CLC 710 ADC #2 720 CMP #&15 730 BCS endprint 740 ASL A 750 TAY 760 LDA index+diff,Y 770 STA address 780 INY 790 LDA index+diff,Y 800 STA address+1 810 LDY #&FF 820 .printloop 830 INY 840 LDA (address),Y 850 BEQ endprint 860 JSR osasci 870 JMP printloop+diff 880 .endprint 890 JSR osnewl 900 PLA 910 STA address+1 920 PLA 930 STA address 940 PLA 950 TAY 960 PLA 970 TAX 980 PLA 990 RTS 1000 .printbyte 1010 PHA 1020 LSR A 1030 LSR A 1040 LSR A 1050 LSR A 1060 JSR nibble+diff 1070 PLA 1080 JSR nibble+diff 1090 LDA #ASC(" ") 1100 JMP osasci 1110 .nibble 1120 AND #&0F 1130 SED 1140 CLC 1150 ADC #&90 1160 ADC #&40 1170 CLD 1180 JMP osasci 1190 .equals 1200 JSR osasci 1210 LDA #ASC("=") 1220 JMP osasci 1230 .index 1240 OPT FNequb((fe+diff) MOD 256) 1250 OPT FNequb((fe+diff) DIV 256) 1260 OPT FNequb((ff+diff) MOD 256) 1270 OPT FNequb((ff+diff) DIV 256) 1280 OPT FNequb((zero+diff) MOD 256) 1290 OPT FNequb((zero+diff) DIV 256) 1300 OPT FNequb((one+diff) MOD 256) 1310 OPT FNequb((one+diff) DIV 256) 1320 OPT FNequb((two+diff) MOD 256) 1330 OPT FNequb((two+diff) DIV 256) 1340 OPT FNequb((three+diff) MOD 256) 1350 OPT FNequb((three+diff) DIV 256) 1360 OPT FNequb((four+diff) MOD 256) 1370 OPT FNequb((four+diff) DIV 256) 1380 OPT FNequb((five+diff) MOD 256) 1390 OPT FNequb((five+diff) DIV 256) 1400 OPT FNequb((six+diff) MOD 256) 1410 OPT FNequb((six+diff) DIV 256) 1420 OPT FNequb((seven+diff) MOD 256) 1430 OPT FNequb((seven+diff) DIV 256) 1440 OPT FNequb((eight+diff) MOD 256) 1450 OPT FNequb((eight+diff) DIV 256) 1460 OPT FNequb((nine+diff) MOD 256) 1470 OPT FNequb((nine+diff) DIV 256) 1480 OPT FNequb((ten+diff) MOD 256) 1490 OPT FNequb((ten+diff) DIV 256) 1500 OPT FNequb((eleven+diff) MOD 256) 1510 OPT FNequb((eleven+diff) DIV 256) 1520 OPT FNequb((twelve+diff) MOD 256) 1530 OPT FNequb((twelve+diff) DIV 256) 1540 OPT FNequb((thirteen+diff) MOD 256) 1550 OPT FNequb((thirteen+diff) DIV 256) 1560 OPT FNequb((fourteen+diff) MOD 256) 1570 OPT FNequb((fourteen+diff) DIV 256) 1580 OPT FNequb((fifteen+diff) MOD 256) 1590 OPT FNequb((fifteen+diff) DIV 256) 1600 OPT FNequb((sixteen+diff) MOD 256) 1610 OPT FNequb((sixteen+diff) DIV 256) 1620 OPT FNequb((seventeen+diff) MOD 256) 1630 OPT FNequb((seventeen+diff) DIV 256) 1640 OPT FNequb((eighteen+diff) MOD 256) 1650 OPT FNequb((eighteen+diff) DIV 256) 1660 .fe 1670 OPT FNequs("Tube system post init.") 1680 BRK 1690 .ff 1700 OPT FNequs("Tube system main init.") 1710 BRK 1720 .zero 1730 OPT FNequs("No operation") 1740 BRK 1750 .one 1760 OPT FNequs("Abs. workspace claim") 1770 BRK 1780 .two 1790 OPT FNequs("Private workspace claim") 1800 BRK 1810 .three 1820 OPT FNequs("Auto-boot") 1830 BRK 1840 .four 1850 OPT FNequs("Unrecognised command") 1860 BRK 1870 .five 1880 OPT FNequs("Unrecognised interupt") 1890 BRK 1900 .six 1910 OPT FNequs("Break") 1920 BRK 1930 .seven 1940 OPT FNequs("Unrecognised Osbyte") 1950 BRK 1960 .eight 1970 OPT FNequs("Unrecognised Osword") 1980 BRK 1990 .nine 2000 OPT FNequs("Help") 2010 BRK 2020 .ten 2030 OPT FNequs("Claim static workspace") 2040 BRK 2050 .eleven 2060 OPT FNequs("NMI release") 2070 BRK 2080 .twelve 2090 OPT FNequs("NMI claim") 2100 BRK 2110 .thirteen 2120 OPT FNequs("RFS initialise") 2130 BRK 2140 .fourteen 2150 OPT FNequs("RFS byte get") 2160 BRK 2170 .fifteen 2180 OPT FNequs("Vectors claimed") 2190 BRK 2200 .sixteen 2210 OPT FNequs("SPOOL/EXEC file closure") 2220 BRK 2230 .seventeen 2240 OPT FNequs("Font implode/explode") 2250 BRK 2260 .eighteen 2270 OPT FNequs("Init. filing system") 2280 BRK 2290 .lastbyte 2300 ] 2310 NEXT 2320 INPUT'"Save filename? : "filename$ 2330 IF filename$="" END 2340 $save="SAVE "+filename$+" "+STR$~(HIMEM)+" "+STR$~(las tbyte)+" FFFF8000 FFFF8000" 2350 X%=save MOD 256 2360 Y%=save DIV 256 2370 *OPT1,2 2380 CALL oscli 2390 *OPT1,0 2400 END 2410 DEFFNequb(byte) 2420 ?P%=byte 2430 P%=P%+1 2440 =pass 2450 DEFFNequw(word) 2460 ?P%=word MOD 256 2470 P%?1=word DIV 256 2480 P%=P%+2 2490 =pass 2500 DEFFNequd(double) 2510 !P%=double 2520 P%=P%+4 2530 =pass 2540 DEFFNequs(string$) 2550 $P%=string$ 2560 P%=P%+LEN(string$) 2570 =pass
00000000 4d 61 73 74 65 72 69 6e 67 20 53 69 64 65 77 61 |Mastering Sidewa| 00000010 79 73 20 52 4f 4d 20 26 20 52 41 4d 20 2d 20 4d |ys ROM & RAM - M| 00000020 6f 64 75 6c 65 20 30 32 20 2d 20 52 6f 6d 20 68 |odule 02 - Rom h| 00000030 65 61 64 65 72 73 0d 2d 2d 2d 2d 2d 2d 2d 2d 2d |eaders.---------| 00000040 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| * 00000060 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 0d 0d 20 |-------------.. | 00000070 20 50 61 67 65 64 20 72 6f 6d 73 20 61 6e 64 20 | Paged roms and | 00000080 73 69 64 65 77 61 79 73 20 72 61 6d 73 20 63 61 |sideways rams ca| 00000090 6e 20 63 6f 6e 74 61 69 6e 20 6c 61 6e 67 75 61 |n contain langua| 000000a0 67 65 73 2c 20 75 74 69 6c 69 74 69 65 73 20 6f |ges, utilities o| 000000b0 72 0d 70 72 6f 67 72 61 6d 73 20 61 6e 64 20 64 |r.programs and d| 000000c0 61 74 61 20 73 74 6f 72 65 64 20 69 6e 20 74 68 |ata stored in th| 000000d0 65 20 52 46 53 2e 20 41 6c 6c 20 72 6f 6d 73 2c |e RFS. All roms,| 000000e0 20 77 68 61 74 65 76 65 72 20 74 68 65 79 20 63 | whatever they c| 000000f0 6f 6e 74 61 69 6e 2c 0d 6d 75 73 74 20 62 65 20 |ontain,.must be | 00000100 72 65 63 6f 67 6e 69 73 65 64 20 62 79 20 74 68 |recognised by th| 00000110 65 20 6f 70 65 72 61 74 69 6e 67 20 73 79 73 74 |e operating syst| 00000120 65 6d 2e 20 54 6f 20 62 65 20 72 65 63 6f 67 6e |em. To be recogn| 00000130 69 73 65 64 20 74 68 65 20 66 69 72 73 74 0d 64 |ised the first.d| 00000140 6f 7a 65 6e 20 6f 72 20 73 6f 20 62 79 74 65 73 |ozen or so bytes| 00000150 20 6d 75 73 74 20 75 73 65 20 74 68 65 20 72 6f | must use the ro| 00000160 6d 20 68 65 61 64 65 72 20 66 6f 72 6d 61 74 20 |m header format | 00000170 73 68 6f 77 6e 20 69 6e 20 66 69 67 75 72 65 20 |shown in figure | 00000180 32 2e 31 2e 0d 54 68 65 20 66 69 72 73 74 20 31 |2.1..The first 1| 00000190 30 20 62 79 74 65 73 20 6f 66 20 74 68 65 20 68 |0 bytes of the h| 000001a0 65 61 64 65 72 20 66 72 6f 6d 20 26 38 30 30 30 |eader from &8000| 000001b0 20 74 6f 20 26 38 30 30 39 20 68 61 76 65 20 66 | to &8009 have f| 000001c0 69 78 65 64 0d 70 6f 73 69 74 69 6f 6e 73 20 69 |ixed.positions i| 000001d0 6e 20 6d 65 6d 6f 72 79 20 61 6e 64 20 6d 75 73 |n memory and mus| 000001e0 74 20 63 6f 6e 66 6f 72 6d 20 77 69 74 68 20 74 |t conform with t| 000001f0 68 65 20 70 61 74 74 65 72 6e 20 73 68 6f 77 6e |he pattern shown| 00000200 20 62 75 74 2c 0d 62 65 63 61 75 73 65 20 74 68 | but,.because th| 00000210 65 20 63 6f 70 79 72 69 67 68 74 20 61 6e 64 20 |e copyright and | 00000220 74 69 74 6c 65 20 73 74 72 69 6e 67 73 20 76 61 |title strings va| 00000230 72 79 20 69 6e 20 6c 65 6e 67 74 68 20 61 6e 64 |ry in length and| 00000240 20 62 65 63 61 75 73 65 0d 73 6f 6d 65 20 6f 66 | because.some of| 00000250 20 74 68 65 20 72 65 73 74 20 6f 66 20 74 68 65 | the rest of the| 00000260 20 68 65 61 64 65 72 20 69 73 20 6f 70 74 69 6f | header is optio| 00000270 6e 61 6c 2c 20 74 68 65 20 68 65 61 64 65 72 20 |nal, the header | 00000280 64 6f 65 73 20 6e 6f 74 20 68 61 76 65 20 61 0d |does not have a.| 00000290 66 69 78 65 64 20 73 69 7a 65 2e 0d 0d 0d 0d 20 |fixed size..... | 000002a0 20 20 20 20 20 20 20 4d 65 6d 6f 72 79 20 6d 61 | Memory ma| 000002b0 70 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |p | 000002c0 4d 65 6d 6f 72 79 20 6d 61 70 0d 20 20 20 20 20 |Memory map. | 000002d0 20 20 20 20 6f 66 20 72 6f 6d 20 20 20 20 20 20 | of rom | 000002e0 20 20 20 20 20 20 20 20 20 20 20 20 6f 66 20 68 | of h| 000002f0 65 61 64 65 72 0d 26 42 46 46 46 20 2b 2d 2d 2d |eader.&BFFF +---| 00000300 2d 2d 2d 2d 2d 2d 2d 2d 2b 20 20 20 20 20 20 2f |--------+ /| 00000310 2b 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |+---------------| 00000320 2d 2d 2d 2d 2d 2d 2d 2d 2b 0d 20 20 20 20 20 20 |--------+. | 00000330 21 20 20 20 20 20 20 20 20 20 20 20 21 20 20 20 |! ! | 00000340 20 20 2f 20 21 54 75 62 65 20 72 65 6c 6f 63 61 | / !Tube reloca| 00000350 74 69 6f 6e 20 61 64 64 72 65 73 73 21 0d 20 20 |tion address!. | 00000360 20 20 20 20 21 20 20 20 20 20 20 20 20 20 20 20 | ! | 00000370 21 20 20 20 20 20 21 20 21 26 30 30 20 20 20 20 |! ! !&00 | 00000380 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000390 21 0d 20 20 20 20 20 20 21 20 20 20 20 20 20 20 |!. ! | 000003a0 20 20 20 20 21 20 20 20 20 2f 20 20 21 43 6f 70 | ! / !Cop| 000003b0 79 72 69 67 68 74 20 73 74 72 69 6e 67 20 20 20 |yright string | 000003c0 20 20 20 20 21 0d 20 20 20 20 20 20 21 20 20 20 | !. ! | 000003d0 20 20 20 20 20 20 20 20 21 20 20 20 20 21 20 20 | ! ! | 000003e0 21 26 30 30 20 20 20 20 20 20 20 20 20 20 20 20 |!&00 | 000003f0 20 20 20 20 20 20 20 20 21 0d 20 20 20 20 20 20 | !. | 00000400 21 20 20 20 20 20 20 20 20 20 20 20 21 20 20 20 |! ! | 00000410 2f 20 20 20 21 4f 70 74 69 6f 6e 61 6c 20 76 65 |/ !Optional ve| 00000420 72 73 69 6f 6e 20 73 74 72 69 6e 67 21 0d 20 20 |rsion string!. | 00000430 20 20 20 20 21 20 20 52 6f 6d 20 63 6f 64 65 20 | ! Rom code | 00000440 21 20 20 20 21 20 20 20 21 26 30 30 20 20 20 20 |! ! !&00 | 00000450 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000460 21 0d 20 20 20 20 20 20 21 20 20 20 20 20 20 20 |!. ! | 00000470 20 20 20 20 21 20 20 2f 20 20 20 20 21 52 6f 6d | ! / !Rom| 00000480 20 74 69 74 6c 65 20 73 74 72 69 6e 67 20 20 20 | title string | 00000490 20 20 20 20 21 20 26 38 30 30 39 2d 20 2e 2e 2e | ! &8009- ...| 000004a0 0d 20 20 20 20 20 20 21 20 20 20 20 20 20 20 20 |. ! | 000004b0 20 20 20 21 20 20 21 20 20 20 20 21 42 69 6e 61 | ! ! !Bina| 000004c0 72 79 20 76 65 72 73 69 6f 6e 20 6e 75 6d 62 65 |ry version numbe| 000004d0 72 20 20 21 20 26 38 30 30 38 0d 20 20 20 20 20 |r ! &8008. | 000004e0 20 2b 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2b 20 2f | +-----------+ /| 000004f0 20 20 20 20 20 21 43 6f 70 79 72 69 67 68 74 20 | !Copyright | 00000500 6f 66 66 73 65 74 20 20 20 20 20 20 20 21 20 26 |offset ! &| 00000510 38 30 30 37 0d 20 20 20 20 20 20 21 49 6e 74 65 |8007. !Inte| 00000520 72 70 72 65 74 65 72 21 20 21 20 20 20 20 20 21 |rpreter! ! !| 00000530 52 6f 6d 20 74 79 70 65 20 62 79 74 65 20 20 20 |Rom type byte | 00000540 20 20 20 20 20 20 20 21 20 26 38 30 30 36 0d 20 | ! &8006. | 00000550 20 20 20 20 20 2b 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d | +----------| 00000560 2d 2b 2f 20 20 20 20 20 20 21 4a 4d 50 20 73 65 |-+/ !JMP se| 00000570 72 76 69 63 65 20 20 20 20 20 20 20 20 20 20 20 |rvice | 00000580 20 21 20 26 38 30 30 33 2d 26 38 30 30 35 0d 20 | ! &8003-&8005. | 00000590 20 20 20 20 20 21 20 20 48 65 61 64 65 72 20 20 | ! Header | 000005a0 20 21 20 20 20 20 20 20 20 21 4a 4d 50 20 6c 61 | ! !JMP la| 000005b0 6e 67 75 61 67 65 20 20 20 20 20 20 20 20 20 20 |nguage | 000005c0 20 21 20 26 38 30 30 30 2d 26 38 30 30 32 0d 26 | ! &8000-&8002.&| 000005d0 38 30 30 30 20 2b 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |8000 +----------| 000005e0 2d 2b 20 2d 20 2d 20 2d 20 2b 2d 2d 2d 2d 2d 2d |-+ - - - +------| 000005f0 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| 00000600 2d 2b 0d 0d 46 69 67 75 72 65 20 32 2e 31 20 54 |-+..Figure 2.1 T| 00000610 68 65 20 52 6f 6d 20 48 65 61 64 65 72 0d 2d 2d |he Rom Header.--| 00000620 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| 00000630 2d 2d 2d 2d 2d 2d 2d 0d 0d 0d 0d 20 20 54 68 65 |-------.... The| 00000640 20 66 69 72 73 74 20 74 68 72 65 65 20 62 79 74 | first three byt| 00000650 65 73 20 6f 66 20 74 68 65 20 72 6f 6d 20 68 65 |es of the rom he| 00000660 61 64 65 72 20 28 26 38 30 30 30 2d 26 38 30 30 |ader (&8000-&800| 00000670 32 29 20 63 6f 6e 74 61 69 6e 20 74 68 65 0d 6c |2) contain the.l| 00000680 61 6e 67 75 61 67 65 20 65 6e 74 72 79 20 70 6f |anguage entry po| 00000690 69 6e 74 20 6f 72 2c 20 69 66 20 74 68 65 20 72 |int or, if the r| 000006a0 6f 6d 20 69 73 20 6e 6f 74 20 61 20 6c 61 6e 67 |om is not a lang| 000006b0 75 61 67 65 2c 20 74 68 65 20 74 68 72 65 65 20 |uage, the three | 000006c0 62 79 74 65 73 0d 77 69 6c 6c 20 61 6c 6c 20 62 |bytes.will all b| 000006d0 65 20 7a 65 72 6f 2e 20 54 68 65 20 66 69 72 73 |e zero. 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T| 000015b0 68 65 20 63 6f 70 79 72 69 67 68 74 20 73 74 72 |he copyright str| 000015c0 69 6e 67 20 69 73 20 65 73 73 65 6e 74 69 61 6c |ing is essential| 000015d0 20 62 65 63 61 75 73 65 20 74 68 65 20 4d 4f 53 | because the MOS| 000015e0 20 75 73 65 73 20 74 68 69 73 20 73 74 72 69 6e | uses this strin| 000015f0 67 0d 74 6f 20 72 65 63 6f 67 6e 69 73 65 20 74 |g.to recognise t| 00001600 68 65 20 72 6f 6d 20 61 6e 64 2c 20 69 66 20 69 |he rom and, if i| 00001610 74 20 64 6f 65 73 20 6e 6f 74 20 65 78 69 73 74 |t does not exist| 00001620 2c 20 74 68 65 20 72 6f 6d 20 77 69 6c 6c 20 62 |, the rom will b| 00001630 65 0d 69 67 6e 6f 72 65 64 20 62 79 20 74 68 65 |e.ignored by the| 00001640 20 4d 4f 53 2e 20 54 68 65 20 66 6f 72 6d 61 74 | MOS. The format| 00001650 20 6d 75 73 74 20 61 6c 77 61 79 73 20 62 65 20 | must always be | 00001660 61 20 7a 65 72 6f 20 62 79 74 65 20 66 6f 6c 6c |a zero byte foll| 00001670 6f 77 65 64 20 62 79 0d 22 28 43 29 22 20 61 6e |owed by."(C)" an| 00001680 64 20 77 68 61 74 65 76 65 72 20 65 6c 73 65 20 |d whatever else | 00001690 79 6f 75 20 77 61 6e 74 20 74 6f 20 69 6e 63 6c |you want to incl| 000016a0 75 64 65 20 61 6e 64 20 74 68 65 6e 20 61 6e 6f |ude and then ano| 000016b0 74 68 65 72 20 7a 65 72 6f 0d 62 79 74 65 2e 20 |ther zero.byte. | 000016c0 54 68 65 20 6d 69 6e 69 6d 75 6d 20 63 6f 70 79 |The minimum copy| 000016d0 72 69 67 68 74 20 73 74 72 69 6e 67 20 69 73 20 |right string is | 000016e0 61 20 7a 65 72 6f 20 62 79 74 65 20 66 6f 6c 6c |a zero byte foll| 000016f0 6f 77 65 64 20 62 79 20 22 28 43 29 22 0d 61 6e |owed by "(C)".an| 00001700 64 20 61 6e 6f 74 68 65 72 20 7a 65 72 6f 20 62 |d another zero b| 00001710 79 74 65 2e 0d 0d 20 20 54 68 65 20 74 75 62 65 |yte... The tube| 00001720 20 72 65 6c 6f 63 61 74 69 6f 6e 20 61 64 64 72 | relocation addr| 00001730 65 73 73 2c 20 69 66 20 70 72 65 73 65 6e 74 2c |ess, if present,| 00001740 20 69 73 20 61 20 34 20 62 79 74 65 20 61 64 64 | is a 4 byte add| 00001750 72 65 73 73 20 61 74 0d 77 68 69 63 68 20 74 68 |ress at.which th| 00001760 65 20 6c 61 6e 67 75 61 67 65 20 70 61 72 74 20 |e language part | 00001770 6f 66 20 74 68 65 20 72 6f 6d 20 68 61 73 20 62 |of the rom has b| 00001780 65 65 6e 20 61 73 73 65 6d 62 6c 65 64 2e 20 54 |een assembled. T| 00001790 75 62 65 20 72 65 6c 6f 63 61 74 69 6f 6e 0d 77 |ube relocation.w| 000017a0 69 6c 6c 20 6e 6f 74 20 62 65 20 63 6f 76 65 72 |ill not be cover| 000017b0 65 64 20 69 6e 20 74 68 69 73 20 63 6f 75 72 73 |ed in this cours| 000017c0 65 2e 0d 0d 20 20 57 72 69 74 69 6e 67 20 74 68 |e... Writing th| 000017d0 65 20 73 6f 75 72 63 65 20 63 6f 64 65 20 66 6f |e source code fo| 000017e0 72 20 74 68 65 20 68 65 61 64 65 72 20 69 73 20 |r the header is | 000017f0 6d 75 63 68 20 65 61 73 69 65 72 20 74 68 61 74 |much easier that| 00001800 20 77 72 69 74 69 6e 67 0d 61 62 6f 75 74 20 69 | writing.about i| 00001810 74 2e 20 54 68 65 20 6f 70 74 69 6f 6e 61 6c 20 |t. The optional | 00001820 76 65 72 73 69 6f 6e 20 73 74 72 69 6e 67 20 68 |version string h| 00001830 61 73 20 62 65 65 6e 20 6c 65 66 74 20 6f 75 74 |as been left out| 00001840 20 6f 66 20 61 6c 6c 20 74 68 65 0d 65 78 61 6d | of all the.exam| 00001850 70 6c 65 20 70 72 6f 67 72 61 6d 73 2e 20 54 68 |ple programs. Th| 00001860 65 20 73 6f 75 72 63 65 20 63 6f 64 65 20 66 6f |e source code fo| 00001870 72 20 74 68 65 20 68 65 61 64 65 72 20 6f 66 20 |r the header of | 00001880 74 68 65 20 70 72 6f 67 72 61 6d 20 54 52 41 43 |the program TRAC| 00001890 45 0d 61 73 73 65 6d 62 6c 65 73 20 61 73 20 73 |E.assembles as s| 000018a0 68 6f 77 6e 20 69 6e 20 66 69 67 75 72 65 20 32 |hown in figure 2| 000018b0 2e 32 2e 20 59 6f 75 20 63 61 6e 20 73 65 65 20 |.2. You can see | 000018c0 74 68 61 74 20 69 74 20 69 73 20 26 32 39 20 62 |that it is &29 b| 000018d0 79 74 65 73 0d 6c 6f 6e 67 20 62 75 74 20 69 74 |ytes.long but it| 000018e0 20 63 6f 75 6c 64 20 62 65 20 73 68 6f 72 74 65 | could be shorte| 000018f0 72 20 69 66 20 69 74 20 75 73 65 64 20 74 68 65 |r if it used the| 00001900 20 6d 69 6e 69 6d 75 6d 20 63 6f 70 79 72 69 67 | minimum copyrig| 00001910 68 74 20 73 74 72 69 6e 67 0d 6f 66 20 22 28 43 |ht string.of "(C| 00001920 29 22 2e 20 46 69 67 75 72 65 20 32 2e 32 20 69 |)". Figure 2.2 i| 00001930 73 20 61 20 42 41 53 49 43 20 32 20 76 65 72 73 |s a BASIC 2 vers| 00001940 69 6f 6e 20 6f 66 20 54 52 41 43 45 20 61 73 73 |ion of TRACE ass| 00001950 65 6d 62 6c 65 64 20 77 69 74 68 20 62 69 74 0d |embled with bit.| 00001960 7a 65 72 6f 20 6f 66 20 74 68 65 20 4f 50 54 20 |zero of the OPT | 00001970 64 69 72 65 63 74 69 76 65 20 73 65 74 2e 0d 0d |directive set...| 00001980 0d 0d 0d 38 30 30 30 20 30 30 20 20 20 20 20 20 |...8000 00 | 00001990 20 45 51 55 42 20 26 30 30 20 20 20 20 20 20 20 | EQUB &00 | 000019a0 20 20 20 20 20 20 20 20 5c 20 4e 6f 20 6c 61 6e | \ No lan| 000019b0 67 75 61 67 65 0d 38 30 30 31 20 30 30 20 20 20 |guage.8001 00 | 000019c0 20 20 20 20 45 51 55 42 20 26 30 30 20 20 20 20 | EQUB &00 | 000019d0 20 20 20 20 20 20 20 20 20 20 20 5c 20 65 6e 74 | \ ent| 000019e0 72 79 20 70 6f 69 6e 74 0d 38 30 30 32 20 30 30 |ry point.8002 00| 000019f0 20 20 20 20 20 20 20 45 51 55 42 20 26 30 30 0d | EQUB &00.| 00001a00 38 30 30 33 20 34 43 20 32 41 20 38 30 20 4a 4d |8003 4C 2A 80 JM| 00001a10 50 20 73 65 72 76 69 63 65 20 20 20 20 20 20 20 |P service | 00001a20 20 20 20 20 20 5c 20 53 65 72 76 69 63 65 20 65 | \ Service e| 00001a30 6e 74 72 79 20 70 6f 69 6e 74 0d 38 30 30 36 20 |ntry point.8006 | 00001a40 38 32 20 20 20 20 20 20 20 45 51 55 42 20 26 38 |82 EQUB &8| 00001a50 32 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |2 | 00001a60 5c 20 52 6f 6d 20 74 79 70 65 20 62 79 74 65 0d |\ Rom type byte.| 00001a70 38 30 30 37 20 30 45 20 20 20 20 20 20 20 45 51 |8007 0E EQ| 00001a80 55 42 20 63 6f 70 79 72 69 67 68 74 20 4d 4f 44 |UB copyright MOD| 00001a90 20 32 35 36 20 5c 20 63 6f 70 79 72 69 67 68 74 | 256 \ copyright| 00001aa0 20 6f 66 66 73 65 74 0d 38 30 30 38 20 30 30 20 | offset.8008 00 | 00001ab0 20 20 20 20 20 20 45 51 55 42 20 26 30 30 20 20 | EQUB &00 | 00001ac0 20 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 42 | \ B| 00001ad0 69 6e 61 72 79 20 76 65 72 73 69 6f 6e 0d 38 30 |inary version.80| 00001ae0 30 39 20 35 34 20 35 32 20 34 31 20 0d 20 20 20 |09 54 52 41 . | 00001af0 20 20 34 33 20 34 35 20 20 20 20 45 51 55 53 20 | 43 45 EQUS | 00001b00 22 54 52 41 43 45 22 20 20 20 20 20 20 20 20 20 |"TRACE" | 00001b10 20 20 5c 20 54 69 74 6c 65 20 73 74 72 69 6e 67 | \ Title string| 00001b20 0d 38 30 30 45 20 20 20 20 20 20 20 20 20 20 2e |.800E .| 00001b30 63 6f 70 79 72 69 67 68 74 0d 38 30 30 45 20 30 |copyright.800E 0| 00001b40 30 20 20 20 20 20 20 20 45 51 55 42 20 26 30 30 |0 EQUB &00| 00001b50 0d 38 30 30 46 20 32 38 20 34 33 20 32 39 20 0d |.800F 28 43 29 .| 00001b60 20 20 20 20 20 32 30 20 34 37 20 36 46 20 0d 20 | 20 47 6F . | 00001b70 20 20 20 20 37 32 20 36 34 20 36 46 20 0d 20 20 | 72 64 6F . | 00001b80 20 20 20 36 45 20 32 30 20 34 38 20 0d 20 20 20 | 6E 20 48 . | 00001b90 20 20 36 46 20 37 32 20 37 33 20 0d 20 20 20 20 | 6F 72 73 . | 00001ba0 20 36 39 20 36 45 20 36 37 20 0d 20 20 20 20 20 | 69 6E 67 . | 00001bb0 37 34 20 36 46 20 36 45 20 0d 20 20 20 20 20 32 |74 6F 6E . 2| 00001bc0 30 20 33 31 20 33 39 20 0d 20 20 20 20 20 33 38 |0 31 39 . 38| 00001bd0 20 33 37 20 20 20 20 45 51 55 53 20 22 28 43 29 | 37 EQUS "(C)| 00001be0 20 47 6f 72 64 6f 6e 20 48 6f 72 73 69 6e 67 74 | Gordon Horsingt| 00001bf0 6f 6e 20 31 39 38 37 22 0d 38 30 32 39 20 30 30 |on 1987".8029 00| 00001c00 20 20 20 20 20 20 20 45 51 55 42 20 26 30 30 0d | EQUB &00.| 00001c10 38 30 32 41 20 20 20 20 20 20 20 20 20 20 2e 73 |802A .s| 00001c20 65 72 76 69 63 65 20 20 20 20 20 20 20 20 20 20 |ervice | 00001c30 20 20 20 20 20 5c 20 53 74 61 72 74 20 6f 66 20 | \ Start of | 00001c40 69 6e 74 65 72 70 72 65 74 65 72 0d 0d 46 69 67 |interpreter..Fig| 00001c50 75 72 65 20 32 2e 32 20 54 68 65 20 72 6f 6d 20 |ure 2.2 The rom | 00001c60 68 65 61 64 65 72 20 6f 66 20 54 52 41 43 45 0d |header of TRACE.| 00001c70 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| * 00001c90 2d 2d 0d 0d 0d 0d 0d 20 20 57 68 65 6e 20 74 68 |--..... When th| 00001ca0 65 20 4d 4f 53 20 72 65 71 75 65 73 74 73 20 74 |e MOS requests t| 00001cb0 68 65 20 70 61 67 65 64 20 72 6f 6d 73 20 74 6f |he paged roms to| 00001cc0 20 70 72 6f 76 69 64 65 20 61 20 73 65 72 76 69 | provide a servi| 00001cd0 63 65 20 74 68 65 0d 68 69 67 68 65 73 74 20 70 |ce the.highest p| 00001ce0 72 69 6f 72 69 74 79 20 72 6f 6d 2c 20 72 6f 6d |riority rom, rom| 00001cf0 20 26 30 46 2c 20 69 73 20 6f 66 66 65 72 65 64 | &0F, is offered| 00001d00 20 74 68 65 20 66 69 72 73 74 20 6f 70 70 6f 72 | the first oppor| 00001d10 74 75 6e 69 74 79 20 74 6f 0d 72 65 73 70 6f 6e |tunity to.respon| 00001d20 64 20 74 6f 20 74 68 65 20 72 65 71 75 65 73 74 |d to the request| 00001d30 2e 20 49 74 20 69 73 20 65 6e 74 65 72 65 64 20 |. It is entered | 00001d40 61 74 20 74 68 65 20 73 65 72 76 69 63 65 20 65 |at the service e| 00001d50 6e 74 72 79 20 70 6f 69 6e 74 20 77 69 74 68 0d |ntry point with.| 00001d60 74 68 65 20 72 65 67 69 73 74 65 72 73 20 73 65 |the registers se| 00001d70 74 20 75 70 20 61 73 20 73 68 6f 77 6e 20 69 6e |t up as shown in| 00001d80 20 66 69 67 75 72 65 20 32 2e 33 2e 0d 0d 0d 0d | figure 2.3.....| 00001d90 0d 52 65 67 69 73 74 65 72 20 20 20 20 20 20 20 |.Register | 00001da0 20 20 20 20 20 53 65 72 76 69 63 65 20 63 61 6c | Service cal| 00001db0 6c 20 69 6e 66 6f 72 6d 61 74 69 6f 6e 0d 2d 2d |l information.--| 00001dc0 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| * 00001df0 2d 2d 2d 2d 2d 2d 2d 2d 0d 41 63 63 75 6d 75 6c |--------.Accumul| 00001e00 61 74 6f 72 20 20 20 20 20 20 20 20 20 53 65 72 |ator Ser| 00001e10 76 69 63 65 20 74 79 70 65 20 72 65 71 75 65 73 |vice type reques| 00001e20 74 65 64 0d 58 20 72 65 67 69 73 74 65 72 20 20 |ted.X register | 00001e30 20 20 20 20 20 20 20 20 4e 75 6d 62 65 72 20 6f | Number o| 00001e40 66 20 63 75 72 72 65 6e 74 20 72 6f 6d 0d 59 20 |f current rom.Y | 00001e50 72 65 67 69 73 74 65 72 20 20 20 20 20 20 20 20 |register | 00001e60 20 20 41 6e 79 20 70 61 72 61 6d 65 74 65 72 20 | Any parameter | 00001e70 72 65 71 75 69 72 65 64 20 66 6f 72 20 74 68 65 |required for the| 00001e80 20 73 65 72 76 69 63 65 0d 0d 0d 46 69 67 75 72 | service...Figur| 00001e90 65 20 32 2e 33 20 53 65 72 76 69 63 65 20 63 61 |e 2.3 Service ca| 00001ea0 6c 6c 20 72 65 67 69 73 74 65 72 73 2e 0d 2d 2d |ll registers..--| 00001eb0 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| * 00001ed0 0d 0d 0d 0d 20 20 49 66 20 72 6f 6d 20 26 30 46 |.... If rom &0F| 00001ee0 20 69 73 20 75 6e 61 62 6c 65 20 74 6f 20 70 72 | is unable to pr| 00001ef0 6f 76 69 64 65 20 74 68 65 20 73 65 72 76 69 63 |ovide the servic| 00001f00 65 20 72 65 71 75 65 73 74 65 64 20 69 74 20 6d |e requested it m| 00001f10 75 73 74 20 65 78 69 74 0d 75 73 69 6e 67 20 52 |ust exit.using R| 00001f20 54 53 20 77 69 74 68 20 61 6c 6c 20 74 68 72 65 |TS with all thre| 00001f30 65 20 72 65 67 69 73 74 65 72 73 20 70 72 65 73 |e registers pres| 00001f40 65 72 76 65 64 20 61 6e 64 20 74 68 65 20 6e 65 |erved and the ne| 00001f50 78 74 20 72 6f 6d 2c 20 72 6f 6d 0d 26 30 45 2c |xt rom, rom.&0E,| 00001f60 20 77 69 6c 6c 20 62 65 20 67 69 76 65 6e 20 74 | will be given t| 00001f70 68 65 20 73 61 6d 65 20 6f 70 70 6f 72 74 75 6e |he same opportun| 00001f80 69 74 79 20 74 6f 20 70 72 6f 76 69 64 65 20 74 |ity to provide t| 00001f90 68 65 20 73 65 72 76 69 63 65 2c 20 61 6e 64 20 |he service, and | 00001fa0 73 6f 0d 6f 6e 20 64 6f 77 6e 20 74 6f 20 72 6f |so.on down to ro| 00001fb0 6d 20 26 30 30 2e 20 49 66 20 61 20 72 6f 6d 20 |m &00. If a rom | 00001fc0 69 73 20 61 62 6c 65 20 74 6f 20 70 72 6f 76 69 |is able to provi| 00001fd0 64 65 20 74 68 65 20 73 65 72 76 69 63 65 20 72 |de the service r| 00001fe0 65 71 75 65 73 74 65 64 2c 0d 61 6e 64 20 64 6f |equested,.and do| 00001ff0 65 73 20 6e 6f 74 20 77 61 6e 74 20 61 6e 79 20 |es not want any | 00002000 6f 74 68 65 72 20 72 6f 6d 20 74 6f 20 61 74 74 |other rom to att| 00002010 65 6d 70 74 20 74 6f 20 70 72 6f 76 69 64 65 20 |empt to provide | 00002020 74 68 65 20 73 61 6d 65 0d 73 65 72 76 69 63 65 |the same.service| 00002030 2c 20 74 68 65 20 61 63 63 75 6d 75 6c 61 74 6f |, the accumulato| 00002040 72 20 73 68 6f 75 6c 64 20 62 65 20 7a 65 72 6f |r should be zero| 00002050 20 6f 6e 20 65 78 69 74 2e 0d 0d 20 20 54 68 65 | on exit... The| 00002060 20 70 72 6f 67 72 61 6d 20 54 52 41 43 45 20 69 | program TRACE i| 00002070 73 20 75 73 65 64 20 74 6f 20 70 72 6f 76 69 64 |s used to provid| 00002080 65 20 61 20 64 69 73 70 6c 61 79 20 6f 66 20 74 |e a display of t| 00002090 68 65 20 73 65 72 76 69 63 65 0d 72 65 71 75 65 |he service.reque| 000020a0 73 74 73 20 6d 61 64 65 20 74 6f 20 74 68 65 20 |sts made to the | 000020b0 73 69 64 65 77 61 79 73 20 72 61 6d 20 62 61 6e |sideways ram ban| 000020c0 6b 20 63 6f 6e 74 61 69 6e 69 6e 67 20 74 68 65 |k containing the| 000020d0 20 6f 62 6a 65 63 74 20 63 6f 64 65 20 69 74 0d | object code it.| 000020e0 67 65 6e 65 72 61 74 65 73 2e 20 43 68 61 69 6e |generates. Chain| 000020f0 20 74 68 65 20 70 72 6f 67 72 61 6d 20 61 6e 64 | the program and| 00002100 2c 20 77 68 65 6e 20 70 72 6f 6d 70 74 65 64 2c |, when prompted,| 00002110 20 67 69 76 65 20 61 20 66 69 6c 65 6e 61 6d 65 | give a filename| 00002120 20 66 6f 72 0d 74 68 65 20 6f 62 6a 65 63 74 20 | for.the object | 00002130 63 6f 64 65 20 77 68 69 63 68 20 77 69 6c 6c 20 |code which will | 00002140 62 65 20 73 61 76 65 64 20 6f 6e 20 64 69 73 63 |be saved on disc| 00002150 20 6f 72 20 74 61 70 65 20 62 65 66 6f 72 65 20 | or tape before | 00002160 79 6f 75 20 6c 6f 61 64 20 69 74 0d 69 6e 74 6f |you load it.into| 00002170 20 53 57 52 2e 20 49 74 20 69 73 20 6e 6f 74 20 | SWR. It is not | 00002180 6e 65 63 65 73 73 61 72 79 20 74 6f 20 69 6e 63 |necessary to inc| 00002190 6c 75 64 65 20 61 20 71 75 6f 74 61 74 69 6f 6e |lude a quotation| 000021a0 20 6d 61 72 6b 20 62 65 66 6f 72 65 20 61 6e 64 | mark before and| 000021b0 0d 61 66 74 65 72 20 74 68 65 20 66 69 6c 65 6e |.after the filen| 000021c0 61 6d 65 2e 20 20 41 66 74 65 72 20 73 61 76 69 |ame. After savi| 000021d0 6e 67 20 74 68 65 20 6f 62 6a 65 63 74 20 63 6f |ng the object co| 000021e0 64 65 2c 20 6c 6f 61 64 20 69 74 20 69 6e 74 6f |de, load it into| 000021f0 20 53 57 52 0d 61 6e 64 20 70 72 65 73 73 20 74 | SWR.and press t| 00002200 68 65 20 42 72 65 61 6b 20 6b 65 79 2e 20 59 6f |he Break key. Yo| 00002210 75 20 77 69 6c 6c 20 69 6d 6d 65 64 69 61 74 65 |u will immediate| 00002220 6c 79 20 73 65 65 20 61 20 64 69 73 70 6c 61 79 |ly see a display| 00002230 20 6f 66 20 74 68 65 0d 73 65 72 76 69 63 65 20 | of the.service | 00002240 72 65 71 75 65 73 74 73 20 73 65 6e 74 20 74 6f |requests sent to| 00002250 20 74 68 65 20 72 6f 6d 73 20 77 68 65 6e 20 62 | the roms when b| 00002260 72 65 61 6b 20 69 73 20 70 72 65 73 73 65 64 2e |reak is pressed.| 00002270 20 54 79 70 65 20 2a 48 45 4c 50 0d 61 6e 64 20 | Type *HELP.and | 00002280 79 6f 75 20 77 69 6c 6c 20 73 65 65 20 74 68 65 |you will see the| 00002290 20 68 65 6c 70 20 73 65 72 76 69 63 65 20 72 65 | help service re| 000022a0 71 75 65 73 74 2e 20 54 79 70 65 20 2a 44 49 53 |quest. Type *DIS| 000022b0 43 20 6f 72 20 2a 52 4f 4d 20 6f 72 0d 77 68 61 |C or *ROM or.wha| 000022c0 74 65 76 65 72 20 65 6c 73 65 20 79 6f 75 20 74 |tever else you t| 000022d0 68 69 6e 6b 20 77 69 6c 6c 20 6d 61 6b 65 20 73 |hink will make s| 000022e0 65 72 76 69 63 65 20 72 65 71 75 65 73 74 73 20 |ervice requests | 000022f0 74 6f 20 74 68 65 20 70 61 67 65 64 20 72 6f 6d |to the paged rom| 00002300 73 0d 61 6e 64 20 79 6f 75 20 77 69 6c 6c 20 73 |s.and you will s| 00002310 6f 6f 6e 20 67 65 74 20 74 6f 20 6b 6e 6f 77 20 |oon get to know | 00002320 74 68 65 20 73 65 72 76 69 63 65 20 72 65 71 75 |the service requ| 00002330 65 73 74 20 63 6f 64 65 73 2e 20 44 6f 20 6e 6f |est codes. Do no| 00002340 74 20 75 73 65 0d 54 52 41 43 45 20 77 68 65 6e |t use.TRACE when| 00002350 20 2a 53 50 4f 4f 4c 69 6e 67 20 6f 72 20 2a 45 | *SPOOLing or *E| 00002360 58 45 43 69 6e 67 20 66 69 6c 65 73 2e 20 49 66 |XECing files. If| 00002370 20 79 6f 75 20 64 6f 20 69 74 20 77 69 6c 6c 20 | you do it will | 00002380 63 61 75 73 65 20 74 68 65 0d 63 6f 6d 70 75 74 |cause the.comput| 00002390 65 72 20 74 6f 20 68 61 6e 67 20 75 70 2e 20 54 |er to hang up. T| 000023a0 68 65 20 73 65 72 76 69 63 65 20 72 65 71 75 65 |he service reque| 000023b0 73 74 20 63 6f 64 65 73 20 61 72 65 20 73 75 6d |st codes are sum| 000023c0 6d 65 72 69 73 65 64 20 69 6e 0d 66 69 67 75 72 |merised in.figur| 000023d0 65 20 32 2e 34 2e 0d 0d 0d 0d 0d 0d 30 30 20 20 |e 2.4.......00 | 000023e0 4e 6f 20 6f 70 65 72 61 74 69 6f 6e 2e 20 41 20 |No operation. A | 000023f0 68 69 67 68 65 72 20 70 72 69 6f 72 69 74 79 20 |higher priority | 00002400 72 6f 6d 20 68 61 73 20 61 6c 72 65 61 64 79 20 |rom has already | 00002410 70 72 6f 76 69 64 65 64 20 74 68 65 0d 73 65 72 |provided the.ser| 00002420 76 69 63 65 20 72 65 71 75 65 73 74 65 64 2e 0d |vice requested..| 00002430 0d 30 31 20 20 41 62 73 6f 6c 75 74 65 20 77 6f |.01 Absolute wo| 00002440 72 6b 73 70 61 63 65 20 63 6c 61 69 6d 2e 20 54 |rkspace claim. T| 00002450 68 69 73 20 77 69 6c 6c 20 62 65 20 64 65 61 6c |his will be deal| 00002460 74 20 77 69 74 68 20 69 6e 20 6d 6f 64 75 6c 65 |t with in module| 00002470 20 31 32 2e 0d 0d 30 32 20 20 50 72 69 76 61 74 | 12...02 Privat| 00002480 65 20 77 6f 72 6b 73 70 61 63 65 20 63 6c 61 69 |e workspace clai| 00002490 6d 2e 20 4d 6f 64 75 6c 65 73 20 31 31 20 61 6e |m. Modules 11 an| 000024a0 64 20 31 33 2e 0d 0d 30 33 20 20 41 75 74 6f 2d |d 13...03 Auto-| 000024b0 62 6f 6f 74 2e 20 4d 6f 64 75 6c 65 73 20 31 39 |boot. Modules 19| 000024c0 2c 20 32 33 2c 20 32 34 2e 0d 0d 30 34 20 20 55 |, 23, 24...04 U| 000024d0 6e 72 65 63 6f 67 6e 69 73 65 64 20 63 6f 6d 6d |nrecognised comm| 000024e0 61 6e 64 2e 20 4d 6f 64 75 6c 65 73 20 33 2c 20 |and. Modules 3, | 000024f0 35 2c 20 38 2c 20 39 2c 20 31 30 2c 20 31 31 2c |5, 8, 9, 10, 11,| 00002500 20 31 33 2c 20 31 35 2c 20 31 36 2c 20 31 37 2c | 13, 15, 16, 17,| 00002510 0d 32 30 2c 20 32 31 2c 20 32 32 2c 20 32 33 2c |.20, 21, 22, 23,| 00002520 20 32 34 2e 0d 0d 30 35 20 20 55 6e 72 65 63 6f | 24...05 Unreco| 00002530 67 6e 69 73 65 64 20 69 6e 74 65 72 75 70 74 2e |gnised interupt.| 00002540 20 4d 6f 64 75 6c 65 20 31 34 2e 0d 0d 30 36 20 | Module 14...06 | 00002550 20 42 72 65 61 6b 2e 20 4d 6f 64 75 6c 65 20 31 | Break. Module 1| 00002560 33 2e 0d 0d 30 37 20 20 55 6e 72 65 63 6f 67 6e |3...07 Unrecogn| 00002570 69 73 65 64 20 4f 73 62 79 74 65 2e 20 4d 6f 64 |ised Osbyte. Mod| 00002580 75 6c 65 20 36 2e 0d 0d 30 38 20 20 55 6e 72 65 |ule 6...08 Unre| 00002590 63 6f 67 6e 69 73 65 64 20 4f 73 77 6f 72 64 2e |cognised Osword.| 000025a0 20 4d 6f 64 75 6c 65 20 37 2e 0d 0d 30 39 20 20 | Module 7...09 | 000025b0 2a 48 45 4c 50 2e 20 4d 6f 64 75 6c 65 73 20 31 |*HELP. Modules 1| 000025c0 36 2c 20 31 37 2c 20 32 33 2c 20 32 34 2e 0d 0d |6, 17, 23, 24...| 000025d0 30 41 20 20 43 6c 61 69 6d 20 73 74 61 74 69 63 |0A Claim static| 000025e0 20 77 6f 72 6b 73 70 61 63 65 2e 20 4d 6f 64 75 | workspace. Modu| 000025f0 6c 65 20 31 32 2e 0d 0d 30 42 20 20 4e 4d 49 20 |le 12...0B NMI | 00002600 72 65 6c 65 61 73 65 2e 20 4e 6f 74 20 63 6f 76 |release. Not cov| 00002610 65 72 65 64 20 69 6e 20 74 68 69 73 20 63 6f 75 |ered in this cou| 00002620 72 73 65 2e 0d 0d 30 43 20 20 4e 4d 49 20 63 6c |rse...0C NMI cl| 00002630 61 69 6d 2e 20 4e 6f 74 20 63 6f 76 65 72 65 64 |aim. Not covered| 00002640 20 69 6e 20 74 68 69 73 20 63 6f 75 72 73 65 2e | in this course.| 00002650 0d 0d 30 44 20 20 52 6f 6d 20 46 69 6c 69 6e 67 |..0D Rom Filing| 00002660 20 53 79 73 74 65 6d 20 69 6e 69 74 69 61 6c 69 | System initiali| 00002670 73 65 2e 20 4d 6f 64 75 6c 65 73 20 31 38 2c 20 |se. Modules 18, | 00002680 31 39 2c 20 32 30 2c 20 32 31 2c 20 32 32 2c 20 |19, 20, 21, 22, | 00002690 32 33 2c 20 32 34 2e 0d 0d 30 45 20 20 52 6f 6d |23, 24...0E Rom| 000026a0 20 46 69 6c 69 6e 67 20 53 79 73 74 65 6d 20 62 | Filing System b| 000026b0 79 74 65 20 67 65 74 2e 20 4d 6f 64 75 6c 65 73 |yte get. Modules| 000026c0 20 31 38 2c 20 31 39 2c 20 32 30 2c 20 32 31 2c | 18, 19, 20, 21,| 000026d0 20 32 32 2c 20 32 33 2c 20 32 34 2e 0d 0d 30 46 | 22, 23, 24...0F| 000026e0 20 20 56 65 63 74 6f 72 73 20 63 6c 61 69 6d 65 | Vectors claime| 000026f0 64 2e 20 4e 6f 74 20 63 6f 76 65 72 65 64 20 69 |d. Not covered i| 00002700 6e 20 74 68 69 73 20 63 6f 75 72 73 65 2e 0d 0d |n this course...| 00002710 31 30 20 20 53 50 4f 4f 4c 2f 45 58 45 43 20 66 |10 SPOOL/EXEC f| 00002720 69 6c 65 20 63 6c 6f 73 75 72 65 20 77 61 72 6e |ile closure warn| 00002730 69 6e 67 2e 20 4e 6f 74 20 63 6f 76 65 72 65 64 |ing. Not covered| 00002740 20 69 6e 20 74 68 69 73 20 63 6f 75 72 73 65 2e | in this course.| 00002750 0d 0d 31 31 20 20 46 6f 6e 74 20 69 6d 70 6c 6f |..11 Font implo| 00002760 73 69 6f 6e 2f 65 78 70 6c 6f 73 69 6f 6e 20 77 |sion/explosion w| 00002770 61 72 6e 69 6e 67 2e 20 4e 6f 74 20 63 6f 76 65 |arning. Not cove| 00002780 72 65 64 20 69 6e 20 74 68 69 73 20 63 6f 75 72 |red in this cour| 00002790 73 65 2e 0d 0d 31 32 20 20 49 6e 69 74 69 61 6c |se...12 Initial| 000027a0 69 73 65 20 66 69 6c 69 6e 67 20 73 79 73 74 65 |ise filing syste| 000027b0 6d 2e 20 4e 6f 74 20 63 6f 76 65 72 65 64 20 69 |m. Not covered i| 000027c0 6e 20 74 68 69 73 20 63 6f 75 72 73 65 2e 0d 0d |n this course...| 000027d0 46 45 20 20 54 75 62 65 20 73 79 73 74 65 6d 20 |FE Tube system | 000027e0 70 6f 73 74 20 69 6e 69 74 69 61 6c 69 73 61 74 |post initialisat| 000027f0 69 6f 6e 2e 20 4d 6f 64 75 6c 65 73 20 31 32 2c |ion. Modules 12,| 00002800 20 32 32 20 28 69 6c 6c 65 67 61 6c 20 75 73 65 | 22 (illegal use| 00002810 29 2e 0d 0d 46 46 20 20 54 75 62 65 20 73 79 73 |)...FF Tube sys| 00002820 74 65 6d 20 6d 61 69 6e 20 69 6e 69 74 69 61 6c |tem main initial| 00002830 69 73 61 74 69 6f 6e 2e 20 4e 6f 74 20 63 6f 76 |isation. Not cov| 00002840 65 72 65 64 20 69 6e 20 74 68 69 73 20 63 6f 75 |ered in this cou| 00002850 72 73 65 2e 0d 0d 0d 46 69 67 75 72 65 20 32 2e |rse....Figure 2.| 00002860 34 20 42 42 43 20 42 20 53 65 72 76 69 63 65 20 |4 BBC B Service | 00002870 72 65 71 75 65 73 74 73 2e 0d 2d 2d 2d 2d 2d 2d |requests..------| 00002880 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| 00002890 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 0d 0d 0d 0d |------------....| 000028a0 0d 20 20 54 68 65 20 70 72 6f 67 72 61 6d 20 54 |. The program T| 000028b0 52 41 43 45 20 77 6f 72 6b 73 20 62 79 20 69 6e |RACE works by in| 000028c0 74 65 72 63 65 70 74 69 6e 67 20 65 76 65 72 79 |tercepting every| 000028d0 20 73 65 72 76 69 63 65 20 72 65 71 75 65 73 74 | service request| 000028e0 20 73 65 6e 74 0d 74 6f 20 74 68 65 20 53 57 52 | sent.to the SWR| 000028f0 2e 20 42 65 66 6f 72 65 20 64 6f 69 6e 67 20 61 |. Before doing a| 00002900 6e 79 74 68 69 6e 67 20 65 6c 73 65 20 69 74 20 |nything else it | 00002910 70 72 65 73 65 72 76 65 73 20 74 68 65 20 41 2c |preserves the A,| 00002920 20 58 20 61 6e 64 20 59 0d 72 65 67 69 73 74 65 | X and Y.registe| 00002930 72 73 20 61 6e 64 20 74 68 65 20 74 77 6f 20 7a |rs and the two z| 00002940 65 72 6f 20 70 61 67 65 20 6d 65 6d 6f 72 79 20 |ero page memory | 00002950 6c 6f 63 61 74 69 6f 6e 73 20 75 73 65 64 20 62 |locations used b| 00002960 79 20 74 68 65 20 70 72 69 6e 74 0d 72 6f 75 74 |y the print.rout| 00002970 69 6e 65 20 62 79 20 70 75 73 68 69 6e 67 20 74 |ine by pushing t| 00002980 68 65 6d 20 6f 6e 20 74 68 65 20 73 74 61 63 6b |hem on the stack| 00002990 20 28 6c 69 6e 65 73 20 33 31 30 2c 33 37 30 29 | (lines 310,370)| 000029a0 2e 20 49 74 20 74 68 65 6e 0d 72 65 74 72 69 65 |. It then.retrie| 000029b0 76 65 73 20 74 68 65 20 73 65 72 76 69 63 65 20 |ves the service | 000029c0 72 65 71 75 65 73 74 20 66 72 6f 6d 20 74 68 65 |request from the| 000029d0 20 73 74 61 63 6b 20 61 6e 64 20 70 75 73 68 65 | stack and pushe| 000029e0 73 20 69 74 20 62 61 63 6b 20 6f 6e 74 6f 0d 74 |s it back onto.t| 000029f0 68 65 20 74 6f 70 20 6f 66 20 74 68 65 20 73 74 |he top of the st| 00002a00 61 63 6b 20 28 6c 69 6e 65 73 20 33 38 30 2d 34 |ack (lines 380-4| 00002a10 30 30 29 20 66 6f 6c 6c 6f 77 65 64 20 62 79 20 |00) followed by | 00002a20 74 68 65 20 59 2c 20 58 20 61 6e 64 20 41 0d 72 |the Y, X and A.r| 00002a30 65 67 69 73 74 65 72 73 20 61 67 61 69 6e 20 28 |egisters again (| 00002a40 6c 69 6e 65 73 20 34 32 30 2d 34 37 30 29 2e 20 |lines 420-470). | 00002a50 49 74 20 74 68 65 6e 20 73 65 6c 65 63 74 73 20 |It then selects | 00002a60 61 20 79 65 6c 6c 6f 77 20 66 6f 72 65 67 72 6f |a yellow foregro| 00002a70 75 6e 64 0d 63 6f 6c 6f 75 72 20 69 66 20 4d 6f |und.colour if Mo| 00002a80 64 65 20 37 20 69 73 20 75 73 65 64 20 28 6c 69 |de 7 is used (li| 00002a90 6e 65 73 20 34 38 30 2d 35 36 30 29 20 61 6e 64 |nes 480-560) and| 00002aa0 20 70 72 69 6e 74 73 20 74 68 65 20 63 6f 6e 74 | prints the cont| 00002ab0 65 6e 74 20 6f 66 20 74 68 65 0d 61 63 63 75 6d |ent of the.accum| 00002ac0 75 6c 61 74 6f 72 2c 20 74 68 65 20 58 20 61 6e |ulator, the X an| 00002ad0 64 20 59 20 72 65 67 69 73 74 65 72 73 20 69 6e |d Y registers in| 00002ae0 20 68 65 78 61 64 65 63 69 6d 61 6c 20 28 6c 69 | hexadecimal (li| 00002af0 6e 65 73 20 35 37 30 2d 36 38 30 29 2e 20 41 6e |nes 570-680). An| 00002b00 0d 65 78 70 6c 61 6e 61 74 69 6f 6e 20 6f 66 20 |.explanation of | 00002b10 74 68 65 20 73 65 72 76 69 63 65 20 72 65 71 75 |the service requ| 00002b20 65 73 74 20 74 79 70 65 20 69 73 20 74 68 65 6e |est type is then| 00002b30 20 67 69 76 65 6e 20 66 6f 72 20 74 68 65 20 42 | given for the B| 00002b40 42 43 20 42 0d 73 65 72 76 69 63 65 20 72 65 71 |BC B.service req| 00002b50 75 65 73 74 73 20 28 6c 69 6e 65 73 20 36 39 30 |uests (lines 690| 00002b60 2d 38 37 30 29 2e 20 54 68 65 20 4d 61 73 74 65 |-870). The Maste| 00002b70 72 20 63 6f 6d 70 75 74 65 72 20 75 73 65 73 20 |r computer uses | 00002b80 73 65 72 76 69 63 65 0d 72 65 71 75 65 73 74 73 |service.requests| 00002b90 20 6e 6f 74 20 61 76 61 69 6c 61 62 6c 65 20 6f | not available o| 00002ba0 6e 20 74 68 65 20 42 42 43 20 42 20 61 6e 64 20 |n the BBC B and | 00002bb0 74 68 65 20 63 6f 6e 74 65 6e 74 20 6f 66 20 74 |the content of t| 00002bc0 68 65 20 72 65 67 69 73 74 65 72 73 0d 66 6f 72 |he registers.for| 00002bd0 20 74 68 65 73 65 20 72 65 71 75 65 73 74 73 20 | these requests | 00002be0 69 73 20 73 68 6f 77 6e 20 62 75 74 20 6e 6f 74 |is shown but not| 00002bf0 20 64 65 73 63 72 69 62 65 64 2e 20 54 68 65 20 | described. The | 00002c00 70 72 6f 67 72 61 6d 20 65 78 69 74 73 20 77 69 |program exits wi| 00002c10 74 68 0d 61 6c 6c 20 74 68 65 20 72 65 67 69 73 |th.all the regis| 00002c20 74 65 72 73 20 61 6e 64 20 6d 65 6d 6f 72 79 20 |ters and memory | 00002c30 6c 6f 63 61 74 69 6f 6e 73 20 72 65 73 74 6f 72 |locations restor| 00002c40 65 64 20 28 6c 69 6e 65 73 20 38 38 30 2d 39 39 |ed (lines 880-99| 00002c50 30 29 2e 0d 0d 20 20 48 61 76 69 6e 67 20 74 68 |0)... Having th| 00002c60 65 20 74 72 61 63 65 20 61 63 74 69 76 65 20 61 |e trace active a| 00002c70 6c 6c 20 74 68 65 20 74 69 6d 65 20 69 73 20 62 |ll the time is b| 00002c80 6f 74 68 20 64 69 73 74 72 61 63 74 69 6e 67 20 |oth distracting | 00002c90 61 6e 64 0d 75 6e 64 65 73 69 72 61 62 6c 65 2e |and.undesirable.| 00002ca0 20 59 6f 75 20 63 61 6e 20 64 69 73 61 62 6c 65 | You can disable| 00002cb0 20 74 68 65 20 75 74 69 6c 69 74 79 20 62 79 20 | the utility by | 00002cc0 72 65 61 64 20 70 72 6f 74 65 63 74 69 6e 67 20 |read protecting | 00002cd0 74 68 65 0d 73 69 64 65 77 61 79 73 20 72 61 6d |the.sideways ram| 00002ce0 20 62 61 6e 6b 20 6f 72 20 62 79 20 6c 6f 61 64 | bank or by load| 00002cf0 69 6e 67 20 73 6f 6d 65 20 6f 74 68 65 72 20 72 |ing some other r| 00002d00 6f 6d 20 69 6d 61 67 65 20 74 6f 20 72 65 70 6c |om image to repl| 00002d10 61 63 65 20 69 74 2e 0d 41 6c 77 61 79 73 20 70 |ace it..Always p| 00002d20 72 65 73 73 20 43 74 72 6c 2b 42 72 65 61 6b 20 |ress Ctrl+Break | 00002d30 61 66 74 65 72 20 72 65 61 64 20 70 72 6f 74 65 |after read prote| 00002d40 63 74 69 6e 67 20 53 57 52 20 6f 72 20 72 65 6c |cting SWR or rel| 00002d50 6f 61 64 69 6e 67 20 61 20 72 6f 6d 0d 69 6d 61 |oading a rom.ima| 00002d60 67 65 2e 0d 0d 20 20 41 6c 74 68 6f 75 67 68 20 |ge... Although | 00002d70 74 68 65 20 4d 61 73 74 65 72 20 63 6f 6d 70 75 |the Master compu| 00002d80 74 65 72 20 75 73 65 73 20 73 65 72 76 69 63 65 |ter uses service| 00002d90 20 72 65 71 75 65 73 74 73 20 74 68 61 74 20 61 | requests that a| 00002da0 72 65 20 6e 6f 74 0d 61 76 61 69 6c 61 62 6c 65 |re not.available| 00002db0 20 6f 6e 20 74 68 65 20 42 20 73 65 72 69 65 73 | on the B series| 00002dc0 20 69 74 20 75 73 65 73 20 61 6c 6c 20 74 68 65 | it uses all the| 00002dd0 20 42 20 73 65 72 69 65 73 20 73 65 72 76 69 63 | B series servic| 00002de0 65 20 72 65 71 75 65 73 74 73 20 61 73 0d 77 65 |e requests as.we| 00002df0 6c 6c 2e 20 46 6f 72 20 74 68 69 73 20 72 65 61 |ll. For this rea| 00002e00 73 6f 6e 20 61 6c 6c 20 70 72 6f 70 65 72 6c 79 |son all properly| 00002e10 20 77 72 69 74 74 65 6e 20 73 6f 66 74 77 61 72 | written softwar| 00002e20 65 20 66 6f 72 20 74 68 65 20 42 42 43 20 42 20 |e for the BBC B | 00002e30 77 69 6c 6c 0d 61 6c 73 6f 20 77 6f 72 6b 20 6f |will.also work o| 00002e40 6e 20 74 68 65 20 4d 61 73 74 65 72 20 62 75 74 |n the Master but| 00002e50 20 69 74 20 77 69 6c 6c 20 6e 6f 74 20 6d 61 6b | it will not mak| 00002e60 65 20 75 73 65 20 6f 66 20 74 68 65 20 74 68 65 |e use of the the| 00002e70 20 65 78 74 72 61 0d 66 61 63 69 6c 69 74 69 65 | extra.facilitie| 00002e80 73 2c 20 73 75 63 68 20 61 73 20 70 61 67 65 64 |s, such as paged| 00002e90 20 77 6f 72 6b 73 70 61 63 65 2c 20 77 69 74 68 | workspace, with| 00002ea0 6f 75 74 20 72 65 73 70 6f 6e 64 69 6e 67 20 74 |out responding t| 00002eb0 6f 20 74 68 65 20 4d 61 73 74 65 72 0d 73 70 65 |o the Master.spe| 00002ec0 63 69 66 69 63 20 73 65 72 76 69 63 65 20 72 65 |cific service re| 00002ed0 71 75 65 73 74 73 2e 0d 0d 0d 0d 0d 0d 0d 0d 20 |quests......... | 00002ee0 20 20 31 30 20 52 45 4d 3a 20 54 52 41 43 45 0d | 10 REM: TRACE.| 00002ef0 20 20 20 32 30 20 4d 4f 44 45 37 0d 20 20 20 33 | 20 MODE7. 3| 00002f00 30 20 48 49 4d 45 4d 3d 26 33 43 30 30 0d 20 20 |0 HIMEM=&3C00. | 00002f10 20 34 30 20 44 49 4d 20 73 61 76 65 20 35 30 0d | 40 DIM save 50.| 00002f20 20 20 20 35 30 20 64 69 66 66 3d 26 38 30 30 30 | 50 diff=&8000| 00002f30 2d 48 49 4d 45 4d 0d 20 20 20 36 30 20 61 64 64 |-HIMEM. 60 add| 00002f40 72 65 73 73 3d 26 37 30 0d 20 20 20 37 30 20 73 |ress=&70. 70 s| 00002f50 74 61 63 6b 3d 26 31 30 35 0d 20 20 20 38 30 20 |tack=&105. 80 | 00002f60 6d 6f 64 65 3d 26 33 35 35 0d 20 20 20 39 30 20 |mode=&355. 90 | 00002f70 6f 73 61 73 63 69 3d 26 46 46 45 33 0d 20 20 31 |osasci=&FFE3. 1| 00002f80 30 30 20 6f 73 6e 65 77 6c 3d 26 46 46 45 37 0d |00 osnewl=&FFE7.| 00002f90 20 20 31 31 30 20 6f 73 63 6c 69 3d 26 46 46 46 | 110 oscli=&FFF| 00002fa0 37 0d 20 20 31 32 30 20 46 4f 52 20 70 61 73 73 |7. 120 FOR pass| 00002fb0 20 3d 20 30 20 54 4f 20 32 20 53 54 45 50 20 32 | = 0 TO 2 STEP 2| 00002fc0 0d 20 20 31 33 30 20 50 25 3d 48 49 4d 45 4d 0d |. 130 P%=HIMEM.| 00002fd0 20 20 31 34 30 20 5b 20 20 20 20 20 20 20 4f 50 | 140 [ OP| 00002fe0 54 20 70 61 73 73 0d 20 20 31 35 30 20 20 20 20 |T pass. 150 | 00002ff0 20 20 20 20 20 42 52 4b 0d 20 20 31 36 30 20 20 | BRK. 160 | 00003000 20 20 20 20 20 20 20 42 52 4b 0d 20 20 31 37 30 | BRK. 170| 00003010 20 20 20 20 20 20 20 20 20 42 52 4b 0d 20 20 31 | BRK. 1| 00003020 38 30 20 20 20 20 20 20 20 20 20 4a 4d 50 20 73 |80 JMP s| 00003030 65 72 76 69 63 65 2b 64 69 66 66 0d 20 20 31 39 |ervice+diff. 19| 00003040 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e |0 OPT FN| 00003050 65 71 75 62 28 26 38 32 29 0d 20 20 32 30 30 20 |equb(&82). 200 | 00003060 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 | OPT FNeq| 00003070 75 62 28 28 63 6f 70 79 72 69 67 68 74 2b 64 69 |ub((copyright+di| 00003080 66 66 29 20 4d 4f 44 20 32 35 36 29 0d 20 20 32 |ff) MOD 256). 2| 00003090 31 30 20 20 20 20 20 20 20 20 20 42 52 4b 0d 20 |10 BRK. | 000030a0 20 32 32 30 20 20 20 20 20 20 20 20 20 4f 50 54 | 220 OPT| 000030b0 20 46 4e 65 71 75 73 28 22 54 52 41 43 45 22 29 | FNequs("TRACE")| 000030c0 0d 20 20 32 33 30 20 2e 63 6f 70 79 72 69 67 68 |. 230 .copyrigh| 000030d0 74 0d 20 20 32 34 30 20 20 20 20 20 20 20 20 20 |t. 240 | 000030e0 42 52 4b 0d 20 20 32 35 30 20 20 20 20 20 20 20 |BRK. 250 | 000030f0 20 20 4f 50 54 20 46 4e 65 71 75 73 28 22 28 43 | OPT FNequs("(C| 00003100 29 20 47 6f 72 64 6f 6e 20 48 6f 72 73 69 6e 67 |) Gordon Horsing| 00003110 74 6f 6e 20 31 39 38 37 22 29 0d 20 20 32 36 30 |ton 1987"). 260| 00003120 20 20 20 20 20 20 20 20 20 42 52 4b 0d 20 20 32 | BRK. 2| 00003130 37 30 20 2e 73 65 72 76 69 63 65 0d 20 20 32 38 |70 .service. 28| 00003140 30 20 20 20 20 20 20 20 20 20 50 48 41 0d 20 20 |0 PHA. | 00003150 32 39 30 20 20 20 20 20 20 20 20 20 54 58 41 0d |290 TXA.| 00003160 20 20 33 30 30 20 20 20 20 20 20 20 20 20 50 48 | 300 PH| 00003170 41 0d 20 20 33 31 30 20 20 20 20 20 20 20 20 20 |A. 310 | 00003180 54 59 41 0d 20 20 33 32 30 20 20 20 20 20 20 20 |TYA. 320 | 00003190 20 20 50 48 41 0d 20 20 33 33 30 20 20 20 20 20 | PHA. 330 | 000031a0 20 20 20 20 4c 44 41 20 61 64 64 72 65 73 73 0d | LDA address.| 000031b0 20 20 33 34 30 20 20 20 20 20 20 20 20 20 50 48 | 340 PH| 000031c0 41 0d 20 20 33 35 30 20 20 20 20 20 20 20 20 20 |A. 350 | 000031d0 53 54 58 20 61 64 64 72 65 73 73 0d 20 20 33 36 |STX address. 36| 000031e0 30 20 20 20 20 20 20 20 20 20 4c 44 41 20 61 64 |0 LDA ad| 000031f0 64 72 65 73 73 2b 31 0d 20 20 33 37 30 20 20 20 |dress+1. 370 | 00003200 20 20 20 20 20 20 50 48 41 0d 20 20 33 38 30 20 | PHA. 380 | 00003210 20 20 20 20 20 20 20 20 54 53 58 0d 20 20 33 39 | TSX. 39| 00003220 30 20 20 20 20 20 20 20 20 20 4c 44 41 20 73 74 |0 LDA st| 00003230 61 63 6b 2c 58 0d 20 20 34 30 30 20 20 20 20 20 |ack,X. 400 | 00003240 20 20 20 20 50 48 41 0d 20 20 34 31 30 20 20 20 | PHA. 410 | 00003250 20 20 20 20 20 20 53 54 41 20 61 64 64 72 65 73 | STA addres| 00003260 73 2b 31 0d 20 20 34 32 30 20 20 20 20 20 20 20 |s+1. 420 | 00003270 20 20 54 59 41 0d 20 20 34 33 30 20 20 20 20 20 | TYA. 430 | 00003280 20 20 20 20 50 48 41 0d 20 20 34 34 30 20 20 20 | PHA. 440 | 00003290 20 20 20 20 20 20 4c 44 41 20 61 64 64 72 65 73 | LDA addres| 000032a0 73 0d 20 20 34 35 30 20 20 20 20 20 20 20 20 20 |s. 450 | 000032b0 50 48 41 0d 20 20 34 36 30 20 20 20 20 20 20 20 |PHA. 460 | 000032c0 20 20 4c 44 41 20 61 64 64 72 65 73 73 2b 31 0d | LDA address+1.| 000032d0 20 20 34 37 30 20 20 20 20 20 20 20 20 20 50 48 | 470 PH| 000032e0 41 0d 20 20 34 38 30 20 20 20 20 20 20 20 20 20 |A. 480 | 000032f0 4c 44 41 20 6d 6f 64 65 0d 20 20 34 39 30 20 20 |LDA mode. 490 | 00003300 20 20 20 20 20 20 20 43 4d 50 20 23 26 30 37 0d | CMP #&07.| 00003310 20 20 35 30 30 20 20 20 20 20 20 20 20 20 42 4e | 500 BN| 00003320 45 20 6e 6f 74 6d 6f 64 65 37 0d 20 20 35 31 30 |E notmode7. 510| 00003330 20 20 20 20 20 20 20 20 20 4c 44 41 20 23 26 38 | LDA #&8| 00003340 33 0d 20 20 35 32 30 20 20 20 20 20 20 20 20 20 |3. 520 | 00003350 42 4e 45 20 73 70 61 63 65 0d 20 20 35 33 30 20 |BNE space. 530 | 00003360 2e 6e 6f 74 6d 6f 64 65 37 0d 20 20 35 34 30 20 |.notmode7. 540 | 00003370 20 20 20 20 20 20 20 20 4c 44 41 20 23 41 53 43 | LDA #ASC| 00003380 28 22 20 22 29 0d 20 20 35 35 30 20 2e 73 70 61 |(" "). 550 .spa| 00003390 63 65 0d 20 20 35 36 30 20 20 20 20 20 20 20 20 |ce. 560 | 000033a0 20 4a 53 52 20 6f 73 61 73 63 69 0d 20 20 35 37 | JSR osasci. 57| 000033b0 30 20 20 20 20 20 20 20 20 20 4c 44 41 20 23 41 |0 LDA #A| 000033c0 53 43 28 22 41 22 29 0d 20 20 35 38 30 20 20 20 |SC("A"). 580 | 000033d0 20 20 20 20 20 20 4a 53 52 20 65 71 75 61 6c 73 | JSR equals| 000033e0 2b 64 69 66 66 0d 20 20 35 39 30 20 20 20 20 20 |+diff. 590 | 000033f0 20 20 20 20 50 4c 41 0d 20 20 36 30 30 20 20 20 | PLA. 600 | 00003400 20 20 20 20 20 20 4a 53 52 20 70 72 69 6e 74 62 | JSR printb| 00003410 79 74 65 2b 64 69 66 66 0d 20 20 36 31 30 20 20 |yte+diff. 610 | 00003420 20 20 20 20 20 20 20 4c 44 41 20 23 41 53 43 28 | LDA #ASC(| 00003430 22 58 22 29 0d 20 20 36 32 30 20 20 20 20 20 20 |"X"). 620 | 00003440 20 20 20 4a 53 52 20 65 71 75 61 6c 73 2b 64 69 | JSR equals+di| 00003450 66 66 0d 20 20 36 33 30 20 20 20 20 20 20 20 20 |ff. 630 | 00003460 20 50 4c 41 0d 20 20 36 34 30 20 20 20 20 20 20 | PLA. 640 | 00003470 20 20 20 4a 53 52 20 70 72 69 6e 74 62 79 74 65 | JSR printbyte| 00003480 2b 64 69 66 66 0d 20 20 36 35 30 20 20 20 20 20 |+diff. 650 | 00003490 20 20 20 20 4c 44 41 20 23 41 53 43 28 22 59 22 | LDA #ASC("Y"| 000034a0 29 0d 20 20 36 36 30 20 20 20 20 20 20 20 20 20 |). 660 | 000034b0 4a 53 52 20 65 71 75 61 6c 73 2b 64 69 66 66 0d |JSR equals+diff.| 000034c0 20 20 36 37 30 20 20 20 20 20 20 20 20 20 50 4c | 670 PL| 000034d0 41 0d 20 20 36 38 30 20 20 20 20 20 20 20 20 20 |A. 680 | 000034e0 4a 53 52 20 70 72 69 6e 74 62 79 74 65 2b 64 69 |JSR printbyte+di| 000034f0 66 66 0d 20 20 36 39 30 20 20 20 20 20 20 20 20 |ff. 690 | 00003500 20 50 4c 41 0d 20 20 37 30 30 20 20 20 20 20 20 | PLA. 700 | 00003510 20 20 20 43 4c 43 0d 20 20 37 31 30 20 20 20 20 | CLC. 710 | 00003520 20 20 20 20 20 41 44 43 20 23 32 0d 20 20 37 32 | ADC #2. 72| 00003530 30 20 20 20 20 20 20 20 20 20 43 4d 50 20 23 26 |0 CMP #&| 00003540 31 35 0d 20 20 37 33 30 20 20 20 20 20 20 20 20 |15. 730 | 00003550 20 42 43 53 20 65 6e 64 70 72 69 6e 74 0d 20 20 | BCS endprint. | 00003560 37 34 30 20 20 20 20 20 20 20 20 20 41 53 4c 20 |740 ASL | 00003570 41 0d 20 20 37 35 30 20 20 20 20 20 20 20 20 20 |A. 750 | 00003580 54 41 59 0d 20 20 37 36 30 20 20 20 20 20 20 20 |TAY. 760 | 00003590 20 20 4c 44 41 20 69 6e 64 65 78 2b 64 69 66 66 | LDA index+diff| 000035a0 2c 59 0d 20 20 37 37 30 20 20 20 20 20 20 20 20 |,Y. 770 | 000035b0 20 53 54 41 20 61 64 64 72 65 73 73 0d 20 20 37 | STA address. 7| 000035c0 38 30 20 20 20 20 20 20 20 20 20 49 4e 59 0d 20 |80 INY. | 000035d0 20 37 39 30 20 20 20 20 20 20 20 20 20 4c 44 41 | 790 LDA| 000035e0 20 69 6e 64 65 78 2b 64 69 66 66 2c 59 0d 20 20 | index+diff,Y. | 000035f0 38 30 30 20 20 20 20 20 20 20 20 20 53 54 41 20 |800 STA | 00003600 61 64 64 72 65 73 73 2b 31 0d 20 20 38 31 30 20 |address+1. 810 | 00003610 20 20 20 20 20 20 20 20 4c 44 59 20 23 26 46 46 | LDY #&FF| 00003620 0d 20 20 38 32 30 20 2e 70 72 69 6e 74 6c 6f 6f |. 820 .printloo| 00003630 70 0d 20 20 38 33 30 20 20 20 20 20 20 20 20 20 |p. 830 | 00003640 49 4e 59 0d 20 20 38 34 30 20 20 20 20 20 20 20 |INY. 840 | 00003650 20 20 4c 44 41 20 28 61 64 64 72 65 73 73 29 2c | LDA (address),| 00003660 59 0d 20 20 38 35 30 20 20 20 20 20 20 20 20 20 |Y. 850 | 00003670 42 45 51 20 65 6e 64 70 72 69 6e 74 0d 20 20 38 |BEQ endprint. 8| 00003680 36 30 20 20 20 20 20 20 20 20 20 4a 53 52 20 6f |60 JSR o| 00003690 73 61 73 63 69 0d 20 20 38 37 30 20 20 20 20 20 |sasci. 870 | 000036a0 20 20 20 20 4a 4d 50 20 70 72 69 6e 74 6c 6f 6f | JMP printloo| 000036b0 70 2b 64 69 66 66 0d 20 20 38 38 30 20 2e 65 6e |p+diff. 880 .en| 000036c0 64 70 72 69 6e 74 0d 20 20 38 39 30 20 20 20 20 |dprint. 890 | 000036d0 20 20 20 20 20 4a 53 52 20 6f 73 6e 65 77 6c 0d | JSR osnewl.| 000036e0 20 20 39 30 30 20 20 20 20 20 20 20 20 20 50 4c | 900 PL| 000036f0 41 0d 20 20 39 31 30 20 20 20 20 20 20 20 20 20 |A. 910 | 00003700 53 54 41 20 61 64 64 72 65 73 73 2b 31 0d 20 20 |STA address+1. | 00003710 39 32 30 20 20 20 20 20 20 20 20 20 50 4c 41 0d |920 PLA.| 00003720 20 20 39 33 30 20 20 20 20 20 20 20 20 20 53 54 | 930 ST| 00003730 41 20 61 64 64 72 65 73 73 0d 20 20 39 34 30 20 |A address. 940 | 00003740 20 20 20 20 20 20 20 20 50 4c 41 0d 20 20 39 35 | PLA. 95| 00003750 30 20 20 20 20 20 20 20 20 20 54 41 59 0d 20 20 |0 TAY. | 00003760 39 36 30 20 20 20 20 20 20 20 20 20 50 4c 41 0d |960 PLA.| 00003770 20 20 39 37 30 20 20 20 20 20 20 20 20 20 54 41 | 970 TA| 00003780 58 0d 20 20 39 38 30 20 20 20 20 20 20 20 20 20 |X. 980 | 00003790 50 4c 41 0d 20 20 39 39 30 20 20 20 20 20 20 20 |PLA. 990 | 000037a0 20 20 52 54 53 0d 20 31 30 30 30 20 2e 70 72 69 | RTS. 1000 .pri| 000037b0 6e 74 62 79 74 65 0d 20 31 30 31 30 20 20 20 20 |ntbyte. 1010 | 000037c0 20 20 20 20 20 50 48 41 0d 20 31 30 32 30 20 20 | PHA. 1020 | 000037d0 20 20 20 20 20 20 20 4c 53 52 20 41 0d 20 31 30 | LSR A. 10| 000037e0 33 30 20 20 20 20 20 20 20 20 20 4c 53 52 20 41 |30 LSR A| 000037f0 0d 20 31 30 34 30 20 20 20 20 20 20 20 20 20 4c |. 1040 L| 00003800 53 52 20 41 0d 20 31 30 35 30 20 20 20 20 20 20 |SR A. 1050 | 00003810 20 20 20 4c 53 52 20 41 0d 20 31 30 36 30 20 20 | LSR A. 1060 | 00003820 20 20 20 20 20 20 20 4a 53 52 20 6e 69 62 62 6c | JSR nibbl| 00003830 65 2b 64 69 66 66 0d 20 31 30 37 30 20 20 20 20 |e+diff. 1070 | 00003840 20 20 20 20 20 50 4c 41 0d 20 31 30 38 30 20 20 | PLA. 1080 | 00003850 20 20 20 20 20 20 20 4a 53 52 20 6e 69 62 62 6c | JSR nibbl| 00003860 65 2b 64 69 66 66 0d 20 31 30 39 30 20 20 20 20 |e+diff. 1090 | 00003870 20 20 20 20 20 4c 44 41 20 23 41 53 43 28 22 20 | LDA #ASC(" | 00003880 22 29 0d 20 31 31 30 30 20 20 20 20 20 20 20 20 |"). 1100 | 00003890 20 4a 4d 50 20 6f 73 61 73 63 69 0d 20 31 31 31 | JMP osasci. 111| 000038a0 30 20 2e 6e 69 62 62 6c 65 0d 20 31 31 32 30 20 |0 .nibble. 1120 | 000038b0 20 20 20 20 20 20 20 20 41 4e 44 20 23 26 30 46 | AND #&0F| 000038c0 0d 20 31 31 33 30 20 20 20 20 20 20 20 20 20 53 |. 1130 S| 000038d0 45 44 0d 20 31 31 34 30 20 20 20 20 20 20 20 20 |ED. 1140 | 000038e0 20 43 4c 43 0d 20 31 31 35 30 20 20 20 20 20 20 | CLC. 1150 | 000038f0 20 20 20 41 44 43 20 23 26 39 30 0d 20 31 31 36 | ADC #&90. 116| 00003900 30 20 20 20 20 20 20 20 20 20 41 44 43 20 23 26 |0 ADC #&| 00003910 34 30 0d 20 31 31 37 30 20 20 20 20 20 20 20 20 |40. 1170 | 00003920 20 43 4c 44 0d 20 31 31 38 30 20 20 20 20 20 20 | CLD. 1180 | 00003930 20 20 20 4a 4d 50 20 6f 73 61 73 63 69 0d 20 31 | JMP osasci. 1| 00003940 31 39 30 20 2e 65 71 75 61 6c 73 0d 20 31 32 30 |190 .equals. 120| 00003950 30 20 20 20 20 20 20 20 20 20 4a 53 52 20 6f 73 |0 JSR os| 00003960 61 73 63 69 0d 20 31 32 31 30 20 20 20 20 20 20 |asci. 1210 | 00003970 20 20 20 4c 44 41 20 23 41 53 43 28 22 3d 22 29 | LDA #ASC("=")| 00003980 0d 20 31 32 32 30 20 20 20 20 20 20 20 20 20 4a |. 1220 J| 00003990 4d 50 20 6f 73 61 73 63 69 0d 20 31 32 33 30 20 |MP osasci. 1230 | 000039a0 2e 69 6e 64 65 78 0d 20 31 32 34 30 20 20 20 20 |.index. 1240 | 000039b0 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 | OPT FNequb(| 000039c0 28 66 65 2b 64 69 66 66 29 20 4d 4f 44 20 32 35 |(fe+diff) MOD 25| 000039d0 36 29 0d 20 31 32 35 30 20 20 20 20 20 20 20 20 |6). 1250 | 000039e0 20 4f 50 54 20 46 4e 65 71 75 62 28 28 66 65 2b | OPT FNequb((fe+| 000039f0 64 69 66 66 29 20 44 49 56 20 32 35 36 29 0d 20 |diff) DIV 256). | 00003a00 31 32 36 30 20 20 20 20 20 20 20 20 20 4f 50 54 |1260 OPT| 00003a10 20 46 4e 65 71 75 62 28 28 66 66 2b 64 69 66 66 | FNequb((ff+diff| 00003a20 29 20 4d 4f 44 20 32 35 36 29 0d 20 31 32 37 30 |) MOD 256). 1270| 00003a30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 | OPT FNe| 00003a40 71 75 62 28 28 66 66 2b 64 69 66 66 29 20 44 49 |qub((ff+diff) DI| 00003a50 56 20 32 35 36 29 0d 20 31 32 38 30 20 20 20 20 |V 256). 1280 | 00003a60 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 | OPT FNequb(| 00003a70 28 7a 65 72 6f 2b 64 69 66 66 29 20 4d 4f 44 20 |(zero+diff) MOD | 00003a80 32 35 36 29 0d 20 31 32 39 30 20 20 20 20 20 20 |256). 1290 | 00003a90 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 7a | OPT FNequb((z| 00003aa0 65 72 6f 2b 64 69 66 66 29 20 44 49 56 20 32 35 |ero+diff) DIV 25| 00003ab0 36 29 0d 20 31 33 30 30 20 20 20 20 20 20 20 20 |6). 1300 | 00003ac0 20 4f 50 54 20 46 4e 65 71 75 62 28 28 6f 6e 65 | OPT FNequb((one| 00003ad0 2b 64 69 66 66 29 20 4d 4f 44 20 32 35 36 29 0d |+diff) MOD 256).| 00003ae0 20 31 33 31 30 20 20 20 20 20 20 20 20 20 4f 50 | 1310 OP| 00003af0 54 20 46 4e 65 71 75 62 28 28 6f 6e 65 2b 64 69 |T FNequb((one+di| 00003b00 66 66 29 20 44 49 56 20 32 35 36 29 0d 20 31 33 |ff) DIV 256). 13| 00003b10 32 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 |20 OPT F| 00003b20 4e 65 71 75 62 28 28 74 77 6f 2b 64 69 66 66 29 |Nequb((two+diff)| 00003b30 20 4d 4f 44 20 32 35 36 29 0d 20 31 33 33 30 20 | MOD 256). 1330 | 00003b40 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 | OPT FNeq| 00003b50 75 62 28 28 74 77 6f 2b 64 69 66 66 29 20 44 49 |ub((two+diff) DI| 00003b60 56 20 32 35 36 29 0d 20 31 33 34 30 20 20 20 20 |V 256). 1340 | 00003b70 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 | OPT FNequb(| 00003b80 28 74 68 72 65 65 2b 64 69 66 66 29 20 4d 4f 44 |(three+diff) MOD| 00003b90 20 32 35 36 29 0d 20 31 33 35 30 20 20 20 20 20 | 256). 1350 | 00003ba0 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 | OPT FNequb((| 00003bb0 74 68 72 65 65 2b 64 69 66 66 29 20 44 49 56 20 |three+diff) DIV | 00003bc0 32 35 36 29 0d 20 31 33 36 30 20 20 20 20 20 20 |256). 1360 | 00003bd0 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 66 | OPT FNequb((f| 00003be0 6f 75 72 2b 64 69 66 66 29 20 4d 4f 44 20 32 35 |our+diff) MOD 25| 00003bf0 36 29 0d 20 31 33 37 30 20 20 20 20 20 20 20 20 |6). 1370 | 00003c00 20 4f 50 54 20 46 4e 65 71 75 62 28 28 66 6f 75 | OPT FNequb((fou| 00003c10 72 2b 64 69 66 66 29 20 44 49 56 20 32 35 36 29 |r+diff) DIV 256)| 00003c20 0d 20 31 33 38 30 20 20 20 20 20 20 20 20 20 4f |. 1380 O| 00003c30 50 54 20 46 4e 65 71 75 62 28 28 66 69 76 65 2b |PT FNequb((five+| 00003c40 64 69 66 66 29 20 4d 4f 44 20 32 35 36 29 0d 20 |diff) MOD 256). | 00003c50 31 33 39 30 20 20 20 20 20 20 20 20 20 4f 50 54 |1390 OPT| 00003c60 20 46 4e 65 71 75 62 28 28 66 69 76 65 2b 64 69 | FNequb((five+di| 00003c70 66 66 29 20 44 49 56 20 32 35 36 29 0d 20 31 34 |ff) DIV 256). 14| 00003c80 30 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 |00 OPT F| 00003c90 4e 65 71 75 62 28 28 73 69 78 2b 64 69 66 66 29 |Nequb((six+diff)| 00003ca0 20 4d 4f 44 20 32 35 36 29 0d 20 31 34 31 30 20 | MOD 256). 1410 | 00003cb0 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 | OPT FNeq| 00003cc0 75 62 28 28 73 69 78 2b 64 69 66 66 29 20 44 49 |ub((six+diff) DI| 00003cd0 56 20 32 35 36 29 0d 20 31 34 32 30 20 20 20 20 |V 256). 1420 | 00003ce0 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 | OPT FNequb(| 00003cf0 28 73 65 76 65 6e 2b 64 69 66 66 29 20 4d 4f 44 |(seven+diff) MOD| 00003d00 20 32 35 36 29 0d 20 31 34 33 30 20 20 20 20 20 | 256). 1430 | 00003d10 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 | OPT FNequb((| 00003d20 73 65 76 65 6e 2b 64 69 66 66 29 20 44 49 56 20 |seven+diff) DIV | 00003d30 32 35 36 29 0d 20 31 34 34 30 20 20 20 20 20 20 |256). 1440 | 00003d40 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 65 | OPT FNequb((e| 00003d50 69 67 68 74 2b 64 69 66 66 29 20 4d 4f 44 20 32 |ight+diff) MOD 2| 00003d60 35 36 29 0d 20 31 34 35 30 20 20 20 20 20 20 20 |56). 1450 | 00003d70 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 65 69 | OPT FNequb((ei| 00003d80 67 68 74 2b 64 69 66 66 29 20 44 49 56 20 32 35 |ght+diff) DIV 25| 00003d90 36 29 0d 20 31 34 36 30 20 20 20 20 20 20 20 20 |6). 1460 | 00003da0 20 4f 50 54 20 46 4e 65 71 75 62 28 28 6e 69 6e | OPT FNequb((nin| 00003db0 65 2b 64 69 66 66 29 20 4d 4f 44 20 32 35 36 29 |e+diff) MOD 256)| 00003dc0 0d 20 31 34 37 30 20 20 20 20 20 20 20 20 20 4f |. 1470 O| 00003dd0 50 54 20 46 4e 65 71 75 62 28 28 6e 69 6e 65 2b |PT FNequb((nine+| 00003de0 64 69 66 66 29 20 44 49 56 20 32 35 36 29 0d 20 |diff) DIV 256). | 00003df0 31 34 38 30 20 20 20 20 20 20 20 20 20 4f 50 54 |1480 OPT| 00003e00 20 46 4e 65 71 75 62 28 28 74 65 6e 2b 64 69 66 | FNequb((ten+dif| 00003e10 66 29 20 4d 4f 44 20 32 35 36 29 0d 20 31 34 39 |f) MOD 256). 149| 00003e20 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e |0 OPT FN| 00003e30 65 71 75 62 28 28 74 65 6e 2b 64 69 66 66 29 20 |equb((ten+diff) | 00003e40 44 49 56 20 32 35 36 29 0d 20 31 35 30 30 20 20 |DIV 256). 1500 | 00003e50 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 00003e60 62 28 28 65 6c 65 76 65 6e 2b 64 69 66 66 29 20 |b((eleven+diff) | 00003e70 4d 4f 44 20 32 35 36 29 0d 20 31 35 31 30 20 20 |MOD 256). 1510 | 00003e80 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 00003e90 62 28 28 65 6c 65 76 65 6e 2b 64 69 66 66 29 20 |b((eleven+diff) | 00003ea0 44 49 56 20 32 35 36 29 0d 20 31 35 32 30 20 20 |DIV 256). 1520 | 00003eb0 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 00003ec0 62 28 28 74 77 65 6c 76 65 2b 64 69 66 66 29 20 |b((twelve+diff) | 00003ed0 4d 4f 44 20 32 35 36 29 0d 20 31 35 33 30 20 20 |MOD 256). 1530 | 00003ee0 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 00003ef0 62 28 28 74 77 65 6c 76 65 2b 64 69 66 66 29 20 |b((twelve+diff) | 00003f00 44 49 56 20 32 35 36 29 0d 20 31 35 34 30 20 20 |DIV 256). 1540 | 00003f10 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 00003f20 62 28 28 74 68 69 72 74 65 65 6e 2b 64 69 66 66 |b((thirteen+diff| 00003f30 29 20 4d 4f 44 20 32 35 36 29 0d 20 31 35 35 30 |) MOD 256). 1550| 00003f40 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 | OPT FNe| 00003f50 71 75 62 28 28 74 68 69 72 74 65 65 6e 2b 64 69 |qub((thirteen+di| 00003f60 66 66 29 20 44 49 56 20 32 35 36 29 0d 20 31 35 |ff) DIV 256). 15| 00003f70 36 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 |60 OPT F| 00003f80 4e 65 71 75 62 28 28 66 6f 75 72 74 65 65 6e 2b |Nequb((fourteen+| 00003f90 64 69 66 66 29 20 4d 4f 44 20 32 35 36 29 0d 20 |diff) MOD 256). | 00003fa0 31 35 37 30 20 20 20 20 20 20 20 20 20 4f 50 54 |1570 OPT| 00003fb0 20 46 4e 65 71 75 62 28 28 66 6f 75 72 74 65 65 | FNequb((fourtee| 00003fc0 6e 2b 64 69 66 66 29 20 44 49 56 20 32 35 36 29 |n+diff) DIV 256)| 00003fd0 0d 20 31 35 38 30 20 20 20 20 20 20 20 20 20 4f |. 1580 O| 00003fe0 50 54 20 46 4e 65 71 75 62 28 28 66 69 66 74 65 |PT FNequb((fifte| 00003ff0 65 6e 2b 64 69 66 66 29 20 4d 4f 44 20 32 35 36 |en+diff) MOD 256| 00004000 29 0d 20 31 35 39 30 20 20 20 20 20 20 20 20 20 |). 1590 | 00004010 4f 50 54 20 46 4e 65 71 75 62 28 28 66 69 66 74 |OPT FNequb((fift| 00004020 65 65 6e 2b 64 69 66 66 29 20 44 49 56 20 32 35 |een+diff) DIV 25| 00004030 36 29 0d 20 31 36 30 30 20 20 20 20 20 20 20 20 |6). 1600 | 00004040 20 4f 50 54 20 46 4e 65 71 75 62 28 28 73 69 78 | OPT FNequb((six| 00004050 74 65 65 6e 2b 64 69 66 66 29 20 4d 4f 44 20 32 |teen+diff) MOD 2| 00004060 35 36 29 0d 20 31 36 31 30 20 20 20 20 20 20 20 |56). 1610 | 00004070 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 73 69 | OPT FNequb((si| 00004080 78 74 65 65 6e 2b 64 69 66 66 29 20 44 49 56 20 |xteen+diff) DIV | 00004090 32 35 36 29 0d 20 31 36 32 30 20 20 20 20 20 20 |256). 1620 | 000040a0 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 28 73 | OPT FNequb((s| 000040b0 65 76 65 6e 74 65 65 6e 2b 64 69 66 66 29 20 4d |eventeen+diff) M| 000040c0 4f 44 20 32 35 36 29 0d 20 31 36 33 30 20 20 20 |OD 256). 1630 | 000040d0 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 | OPT FNequb| 000040e0 28 28 73 65 76 65 6e 74 65 65 6e 2b 64 69 66 66 |((seventeen+diff| 000040f0 29 20 44 49 56 20 32 35 36 29 0d 20 31 36 34 30 |) DIV 256). 1640| 00004100 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 | OPT FNe| 00004110 71 75 62 28 28 65 69 67 68 74 65 65 6e 2b 64 69 |qub((eighteen+di| 00004120 66 66 29 20 4d 4f 44 20 32 35 36 29 0d 20 31 36 |ff) MOD 256). 16| 00004130 35 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 |50 OPT F| 00004140 4e 65 71 75 62 28 28 65 69 67 68 74 65 65 6e 2b |Nequb((eighteen+| 00004150 64 69 66 66 29 20 44 49 56 20 32 35 36 29 0d 20 |diff) DIV 256). | 00004160 31 36 36 30 20 2e 66 65 0d 20 31 36 37 30 20 20 |1660 .fe. 1670 | 00004170 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 00004180 73 28 22 54 75 62 65 20 73 79 73 74 65 6d 20 70 |s("Tube system p| 00004190 6f 73 74 20 69 6e 69 74 2e 22 29 0d 20 31 36 38 |ost init."). 168| 000041a0 30 20 20 20 20 20 20 20 20 20 42 52 4b 0d 20 31 |0 BRK. 1| 000041b0 36 39 30 20 2e 66 66 0d 20 31 37 30 30 20 20 20 |690 .ff. 1700 | 000041c0 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 73 | OPT FNequs| 000041d0 28 22 54 75 62 65 20 73 79 73 74 65 6d 20 6d 61 |("Tube system ma| 000041e0 69 6e 20 69 6e 69 74 2e 22 29 0d 20 31 37 31 30 |in init."). 1710| 000041f0 20 20 20 20 20 20 20 20 20 42 52 4b 0d 20 31 37 | BRK. 17| 00004200 32 30 20 2e 7a 65 72 6f 0d 20 31 37 33 30 20 20 |20 .zero. 1730 | 00004210 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 00004220 73 28 22 4e 6f 20 6f 70 65 72 61 74 69 6f 6e 22 |s("No operation"| 00004230 29 0d 20 31 37 34 30 20 20 20 20 20 20 20 20 20 |). 1740 | 00004240 42 52 4b 0d 20 31 37 35 30 20 2e 6f 6e 65 0d 20 |BRK. 1750 .one. | 00004250 31 37 36 30 20 20 20 20 20 20 20 20 20 4f 50 54 |1760 OPT| 00004260 20 46 4e 65 71 75 73 28 22 41 62 73 2e 20 77 6f | FNequs("Abs. wo| 00004270 72 6b 73 70 61 63 65 20 63 6c 61 69 6d 22 29 0d |rkspace claim").| 00004280 20 31 37 37 30 20 20 20 20 20 20 20 20 20 42 52 | 1770 BR| 00004290 4b 0d 20 31 37 38 30 20 2e 74 77 6f 0d 20 31 37 |K. 1780 .two. 17| 000042a0 39 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 |90 OPT F| 000042b0 4e 65 71 75 73 28 22 50 72 69 76 61 74 65 20 77 |Nequs("Private w| 000042c0 6f 72 6b 73 70 61 63 65 20 63 6c 61 69 6d 22 29 |orkspace claim")| 000042d0 0d 20 31 38 30 30 20 20 20 20 20 20 20 20 20 42 |. 1800 B| 000042e0 52 4b 0d 20 31 38 31 30 20 2e 74 68 72 65 65 0d |RK. 1810 .three.| 000042f0 20 31 38 32 30 20 20 20 20 20 20 20 20 20 4f 50 | 1820 OP| 00004300 54 20 46 4e 65 71 75 73 28 22 41 75 74 6f 2d 62 |T FNequs("Auto-b| 00004310 6f 6f 74 22 29 0d 20 31 38 33 30 20 20 20 20 20 |oot"). 1830 | 00004320 20 20 20 20 42 52 4b 0d 20 31 38 34 30 20 2e 66 | BRK. 1840 .f| 00004330 6f 75 72 0d 20 31 38 35 30 20 20 20 20 20 20 20 |our. 1850 | 00004340 20 20 4f 50 54 20 46 4e 65 71 75 73 28 22 55 6e | OPT FNequs("Un| 00004350 72 65 63 6f 67 6e 69 73 65 64 20 63 6f 6d 6d 61 |recognised comma| 00004360 6e 64 22 29 0d 20 31 38 36 30 20 20 20 20 20 20 |nd"). 1860 | 00004370 20 20 20 42 52 4b 0d 20 31 38 37 30 20 2e 66 69 | BRK. 1870 .fi| 00004380 76 65 0d 20 31 38 38 30 20 20 20 20 20 20 20 20 |ve. 1880 | 00004390 20 4f 50 54 20 46 4e 65 71 75 73 28 22 55 6e 72 | OPT FNequs("Unr| 000043a0 65 63 6f 67 6e 69 73 65 64 20 69 6e 74 65 72 75 |ecognised interu| 000043b0 70 74 22 29 0d 20 31 38 39 30 20 20 20 20 20 20 |pt"). 1890 | 000043c0 20 20 20 42 52 4b 0d 20 31 39 30 30 20 2e 73 69 | BRK. 1900 .si| 000043d0 78 0d 20 31 39 31 30 20 20 20 20 20 20 20 20 20 |x. 1910 | 000043e0 4f 50 54 20 46 4e 65 71 75 73 28 22 42 72 65 61 |OPT FNequs("Brea| 000043f0 6b 22 29 0d 20 31 39 32 30 20 20 20 20 20 20 20 |k"). 1920 | 00004400 20 20 42 52 4b 0d 20 31 39 33 30 20 2e 73 65 76 | BRK. 1930 .sev| 00004410 65 6e 0d 20 31 39 34 30 20 20 20 20 20 20 20 20 |en. 1940 | 00004420 20 4f 50 54 20 46 4e 65 71 75 73 28 22 55 6e 72 | OPT FNequs("Unr| 00004430 65 63 6f 67 6e 69 73 65 64 20 4f 73 62 79 74 65 |ecognised Osbyte| 00004440 22 29 0d 20 31 39 35 30 20 20 20 20 20 20 20 20 |"). 1950 | 00004450 20 42 52 4b 0d 20 31 39 36 30 20 2e 65 69 67 68 | BRK. 1960 .eigh| 00004460 74 0d 20 31 39 37 30 20 20 20 20 20 20 20 20 20 |t. 1970 | 00004470 4f 50 54 20 46 4e 65 71 75 73 28 22 55 6e 72 65 |OPT FNequs("Unre| 00004480 63 6f 67 6e 69 73 65 64 20 4f 73 77 6f 72 64 22 |cognised Osword"| 00004490 29 0d 20 31 39 38 30 20 20 20 20 20 20 20 20 20 |). 1980 | 000044a0 42 52 4b 0d 20 31 39 39 30 20 2e 6e 69 6e 65 0d |BRK. 1990 .nine.| 000044b0 20 32 30 30 30 20 20 20 20 20 20 20 20 20 4f 50 | 2000 OP| 000044c0 54 20 46 4e 65 71 75 73 28 22 48 65 6c 70 22 29 |T FNequs("Help")| 000044d0 0d 20 32 30 31 30 20 20 20 20 20 20 20 20 20 42 |. 2010 B| 000044e0 52 4b 0d 20 32 30 32 30 20 2e 74 65 6e 0d 20 32 |RK. 2020 .ten. 2| 000044f0 30 33 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 |030 OPT | 00004500 46 4e 65 71 75 73 28 22 43 6c 61 69 6d 20 73 74 |FNequs("Claim st| 00004510 61 74 69 63 20 77 6f 72 6b 73 70 61 63 65 22 29 |atic workspace")| 00004520 0d 20 32 30 34 30 20 20 20 20 20 20 20 20 20 42 |. 2040 B| 00004530 52 4b 0d 20 32 30 35 30 20 2e 65 6c 65 76 65 6e |RK. 2050 .eleven| 00004540 0d 20 32 30 36 30 20 20 20 20 20 20 20 20 20 4f |. 2060 O| 00004550 50 54 20 46 4e 65 71 75 73 28 22 4e 4d 49 20 72 |PT FNequs("NMI r| 00004560 65 6c 65 61 73 65 22 29 0d 20 32 30 37 30 20 20 |elease"). 2070 | 00004570 20 20 20 20 20 20 20 42 52 4b 0d 20 32 30 38 30 | BRK. 2080| 00004580 20 2e 74 77 65 6c 76 65 0d 20 32 30 39 30 20 20 | .twelve. 2090 | 00004590 20 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 | OPT FNequ| 000045a0 73 28 22 4e 4d 49 20 63 6c 61 69 6d 22 29 0d 20 |s("NMI claim"). | 000045b0 32 31 30 30 20 20 20 20 20 20 20 20 20 42 52 4b |2100 BRK| 000045c0 0d 20 32 31 31 30 20 2e 74 68 69 72 74 65 65 6e |. 2110 .thirteen| 000045d0 0d 20 32 31 32 30 20 20 20 20 20 20 20 20 20 4f |. 2120 O| 000045e0 50 54 20 46 4e 65 71 75 73 28 22 52 46 53 20 69 |PT FNequs("RFS i| 000045f0 6e 69 74 69 61 6c 69 73 65 22 29 0d 20 32 31 33 |nitialise"). 213| 00004600 30 20 20 20 20 20 20 20 20 20 42 52 4b 0d 20 32 |0 BRK. 2| 00004610 31 34 30 20 2e 66 6f 75 72 74 65 65 6e 0d 20 32 |140 .fourteen. 2| 00004620 31 35 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 |150 OPT | 00004630 46 4e 65 71 75 73 28 22 52 46 53 20 62 79 74 65 |FNequs("RFS byte| 00004640 20 67 65 74 22 29 0d 20 32 31 36 30 20 20 20 20 | get"). 2160 | 00004650 20 20 20 20 20 42 52 4b 0d 20 32 31 37 30 20 2e | BRK. 2170 .| 00004660 66 69 66 74 65 65 6e 0d 20 32 31 38 30 20 20 20 |fifteen. 2180 | 00004670 20 20 20 20 20 20 4f 50 54 20 46 4e 65 71 75 73 | OPT FNequs| 00004680 28 22 56 65 63 74 6f 72 73 20 63 6c 61 69 6d 65 |("Vectors claime| 00004690 64 22 29 0d 20 32 31 39 30 20 20 20 20 20 20 20 |d"). 2190 | 000046a0 20 20 42 52 4b 0d 20 32 32 30 30 20 2e 73 69 78 | BRK. 2200 .six| 000046b0 74 65 65 6e 0d 20 32 32 31 30 20 20 20 20 20 20 |teen. 2210 | 000046c0 20 20 20 4f 50 54 20 46 4e 65 71 75 73 28 22 53 | OPT FNequs("S| 000046d0 50 4f 4f 4c 2f 45 58 45 43 20 66 69 6c 65 20 63 |POOL/EXEC file c| 000046e0 6c 6f 73 75 72 65 22 29 0d 20 32 32 32 30 20 20 |losure"). 2220 | 000046f0 20 20 20 20 20 20 20 42 52 4b 0d 20 32 32 33 30 | BRK. 2230| 00004700 20 2e 73 65 76 65 6e 74 65 65 6e 0d 20 32 32 34 | .seventeen. 224| 00004710 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e |0 OPT FN| 00004720 65 71 75 73 28 22 46 6f 6e 74 20 69 6d 70 6c 6f |equs("Font implo| 00004730 64 65 2f 65 78 70 6c 6f 64 65 22 29 0d 20 32 32 |de/explode"). 22| 00004740 35 30 20 20 20 20 20 20 20 20 20 42 52 4b 0d 20 |50 BRK. | 00004750 32 32 36 30 20 2e 65 69 67 68 74 65 65 6e 0d 20 |2260 .eighteen. | 00004760 32 32 37 30 20 20 20 20 20 20 20 20 20 4f 50 54 |2270 OPT| 00004770 20 46 4e 65 71 75 73 28 22 49 6e 69 74 2e 20 66 | FNequs("Init. f| 00004780 69 6c 69 6e 67 20 73 79 73 74 65 6d 22 29 0d 20 |iling system"). | 00004790 32 32 38 30 20 20 20 20 20 20 20 20 20 42 52 4b |2280 BRK| 000047a0 0d 20 32 32 39 30 20 2e 6c 61 73 74 62 79 74 65 |. 2290 .lastbyte| 000047b0 0d 20 32 33 30 30 20 5d 0d 20 32 33 31 30 20 4e |. 2300 ]. 2310 N| 000047c0 45 58 54 0d 20 32 33 32 30 20 49 4e 50 55 54 27 |EXT. 2320 INPUT'| 000047d0 22 53 61 76 65 20 66 69 6c 65 6e 61 6d 65 3f 20 |"Save filename? | 000047e0 3a 20 22 66 69 6c 65 6e 61 6d 65 24 0d 20 32 33 |: "filename$. 23| 000047f0 33 30 20 49 46 20 66 69 6c 65 6e 61 6d 65 24 3d |30 IF filename$=| 00004800 22 22 20 45 4e 44 0d 20 32 33 34 30 20 24 73 61 |"" END. 2340 $sa| 00004810 76 65 3d 22 53 41 56 45 20 22 2b 66 69 6c 65 6e |ve="SAVE "+filen| 00004820 61 6d 65 24 2b 22 20 22 2b 53 54 52 24 7e 28 48 |ame$+" "+STR$~(H| 00004830 49 4d 45 4d 29 2b 22 20 22 2b 53 54 52 24 7e 28 |IMEM)+" "+STR$~(| 00004840 6c 61 73 0d 20 20 20 20 20 20 74 62 79 74 65 29 |las. tbyte)| 00004850 2b 22 20 46 46 46 46 38 30 30 30 20 46 46 46 46 |+" FFFF8000 FFFF| 00004860 38 30 30 30 22 0d 20 32 33 35 30 20 58 25 3d 73 |8000". 2350 X%=s| 00004870 61 76 65 20 4d 4f 44 20 32 35 36 0d 20 32 33 36 |ave MOD 256. 236| 00004880 30 20 59 25 3d 73 61 76 65 20 44 49 56 20 32 35 |0 Y%=save DIV 25| 00004890 36 0d 20 32 33 37 30 20 2a 4f 50 54 31 2c 32 0d |6. 2370 *OPT1,2.| 000048a0 20 32 33 38 30 20 43 41 4c 4c 20 6f 73 63 6c 69 | 2380 CALL oscli| 000048b0 0d 20 32 33 39 30 20 2a 4f 50 54 31 2c 30 0d 20 |. 2390 *OPT1,0. | 000048c0 32 34 30 30 20 45 4e 44 0d 20 32 34 31 30 20 44 |2400 END. 2410 D| 000048d0 45 46 46 4e 65 71 75 62 28 62 79 74 65 29 0d 20 |EFFNequb(byte). | 000048e0 32 34 32 30 20 3f 50 25 3d 62 79 74 65 0d 20 32 |2420 ?P%=byte. 2| 000048f0 34 33 30 20 50 25 3d 50 25 2b 31 0d 20 32 34 34 |430 P%=P%+1. 244| 00004900 30 20 3d 70 61 73 73 0d 20 32 34 35 30 20 44 45 |0 =pass. 2450 DE| 00004910 46 46 4e 65 71 75 77 28 77 6f 72 64 29 0d 20 32 |FFNequw(word). 2| 00004920 34 36 30 20 3f 50 25 3d 77 6f 72 64 20 4d 4f 44 |460 ?P%=word MOD| 00004930 20 32 35 36 0d 20 32 34 37 30 20 50 25 3f 31 3d | 256. 2470 P%?1=| 00004940 77 6f 72 64 20 44 49 56 20 32 35 36 0d 20 32 34 |word DIV 256. 24| 00004950 38 30 20 50 25 3d 50 25 2b 32 0d 20 32 34 39 30 |80 P%=P%+2. 2490| 00004960 20 3d 70 61 73 73 0d 20 32 35 30 30 20 44 45 46 | =pass. 2500 DEF| 00004970 46 4e 65 71 75 64 28 64 6f 75 62 6c 65 29 0d 20 |FNequd(double). | 00004980 32 35 31 30 20 21 50 25 3d 64 6f 75 62 6c 65 0d |2510 !P%=double.| 00004990 20 32 35 32 30 20 50 25 3d 50 25 2b 34 0d 20 32 | 2520 P%=P%+4. 2| 000049a0 35 33 30 20 3d 70 61 73 73 0d 20 32 35 34 30 20 |530 =pass. 2540 | 000049b0 44 45 46 46 4e 65 71 75 73 28 73 74 72 69 6e 67 |DEFFNequs(string| 000049c0 24 29 0d 20 32 35 35 30 20 24 50 25 3d 73 74 72 |$). 2550 $P%=str| 000049d0 69 6e 67 24 0d 20 32 35 36 30 20 50 25 3d 50 25 |ing$. 2560 P%=P%| 000049e0 2b 4c 45 4e 28 73 74 72 69 6e 67 24 29 0d 20 32 |+LEN(string$). 2| 000049f0 35 37 30 20 3d 70 61 73 73 0d |570 =pass.| 000049fa