Home » CEEFAX disks » telesoftware11.adl » 27-11-88/T\SWR21
27-11-88/T\SWR21
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 » telesoftware11.adl |
Filename: | 27-11-88/T\SWR21 |
Read OK: | ✔ |
File size: | 2530 bytes |
Load address: | 0000 |
Exec address: | FFFFFFFF |
Duplicates
There is 1 duplicate copy of this file in the archive:
- CEEFAX disks » telesoftware11.adl » 27-11-88/T\SWR21
- CEEFAX disks » telesoftware6.adl » 28-03-88/T\SWR21
File contents
Mastering Sideways ROM & RAM - Module 21 - RFS language rom ----------------------------------------------------------- In Module 20 you were shown one way in which programs stored in the RFS can be run with * commands. The programs used to demonstrate the technique created a service rom image. In this module I will show you how a language rom design can be used to achieve a similar effect. One reason why you might choose to implement an RFS language rom is that it will enable you to design a so called turnkey system as well as allow you to run the RFS software with a new * command. A turnkey computer system is one which automatically runs custom software when it is switched on. If you have a language rom in socket &0F, or in a battery backed-up sideways ram socket &0F, then that rom image will be booted when the computer is switched on and when Ctrl+Break is pressed. This is true for all language roms in the highest priority rom socket but, if your custom software is written in BASIC, you would normally have to re-write your program as an independant machine code language to run it in this way. Using an RFS language rom will allow you to use your software in a turnkey system without translating it into an independant machine code program. An RFS language rom can be used in socket &0F of the BBC B simply by moving the other rom chips to make room for it. On the BBC B+ it is necessary to alter link S13 (to the right of IC46) to give the highest priority rom socket on the circuit board priority over BASIC. The RFS language rom image can be configured as the start up language on the Master by using the *CONFIGURE LANG <rom number> command. The RFS language rom can also be used in a lower priority socket than BASIC when it will function like any other language rom and it will be selected when called with *FX142,n or its * command. In the program RFSERV the interpreter passed control to a service routine which selected the RFS, stored a Chain command in the keyboard buffer, and then entered BASIC which executed the command in the keyboard buffer. The program RFSLANG achieves the same result by entering a language which eventually executes the same coding used by the service routine in RFSERV. The one command interpreter is used in the program RFSLANG to compare an unrecognised command with the title string of the rom. If a match is found the rom uses Osbyte &8E to enter the rom at its language entry point. When the rom is entered at its language entry point it must first enable interupts, reset the stack, and re-vector the break vector to point to an error handling routine (see module 17). The complete language coding from RFSLANG is shown in figure 21.1 .language CLI \ enable interupt requests LDX #&FF TXS \ reset stack LDA #basic MOD 256 \ low byte of enter BASIC address STA &202 \ store in Break vector low byte LDA #basic DIV 256 \ high byte of enter BASIC address STA &203 \ store in Break vector high byte LDA #&8D \ Osbyte &8D JSR &FFF4 \ *ROM LDA #&8B \ Osbyte &8B LDX #1 LDY #0 JSR &FFF4 \ *OPT 1,0 LDA #&0F \ Osbyte &0F LDX #0 JSR &FFF4 \ flush all buffers LDA #&FF \ initialise offset PHA \ store offset .keyboard PLA \ restore offset TAX \ transfer offset to X INX \ increment offset TXA \ copy offset to A PHA \ store offset LDY rfscomm,X \ load character BEQ basic \ branch if end of text character LDA #&8A \ Osbyte &8A LDX #0 JSR &FFF4 \ character into keyboard buffer JMP keyboard \ go for next character .basic LDA #&BB \ Osbyte &BB LDX #0 LDY #&FF JSR &FFF4 \ find BASIC LDA #&8E \ Osbyte &8E JMP &FFF4 \ enter BASIC no return . . . .rfscomm EQUS "CHAIN""DEMO""" \ chain command for BASIC EQUB &0D \ <Return> BRK \ end of text marker Figure 21.1 The language coding from RFSLANG. ----------- --------------------------------- The break vector in RFSLANG points to the code which finds and enters BASIC so that, if an error is generated while the language is active, it responds by entering BASIC. The language defined by RFSLANG will only ever be active for a few milli-seconds before it selects BASIC to replace it and generating an error is quite unlikely. I have been unable to generate an error within the language when testing the program. This short cut method of dealing with errors by ignoring them means that the rom will need to be re-booted if they occur. After initialising the language the coding does the same job as the service routine in RFSERV. It selects the RFS, inserts the Chain command into the keyboard buffer, and finds and enters BASIC. When BASIC is entered in this way it executes the command in the keyboard buffer and chains the file from the RFS. The program RFSLANG must be used with the formatting program RFSGEN and whatever programs you want to store in the RFS. These programs are used to create the RFS rom image and detailed instructions on using them were included in Module 18. RFSLANG was written to be used with the supplied demonstration program DEMO. If you want to use it with any other program you will need to alter the command string in lines 1310 to 1330. You can also alter the rom title string in line 220 if you would prefer to select the language with a command other than *RFS. 10 REM: RFSLANG 20 MODE7 30 HIMEM=&3C00 40 diff=&8000-HIMEM 50 H%=HIMEM 60 comvec=&F2 70 romnumber=&F4 80 phrom=&F5 90 rompoint=&F6 100 breakv=&202 110 gsread=&FFC5 120 osbyte=&FFF4 130 FOR pass = 0 TO 2 STEP 2 140 P%=HIMEM 150 [ OPT pass 160 JMP language+diff 170 JMP service+diff 180 OPT FNequb(&C2) 190 OPT FNequb((copyright+diff) MOD 256) 200 BRK 210 .title 220 OPT FNequs("RFS") 230 .copyright 240 BRK 250 OPT FNequs("(C) Gordon Horsington 1987") 260 BRK 270 .service 280 PHA 290 CMP #4 300 BNE trythirteen 310 TXA 320 PHA 330 TYA 340 PHA 350 LDX #&FF 360 .comloop 370 INX 380 LDA title+diff,X 390 BEQ found 400 LDA (comvec),Y 410 INY 420 CMP #ASC(".") 430 BEQ found 440 AND #&DF 450 CMP title+diff,X 460 BEQ comloop 470 PLA 480 TAY 490 PLA 500 TAX 510 PLA 520 RTS 530 .found 540 LDA #&8E 550 LDX romnumber 560 JMP osbyte \ Enter this ROM 570 .trythirteen 580 CMP #13 590 BNE fourteen 600 TYA 610 EOR #&F 620 CMP romnumber 630 BCC out 640 LDA #(lastbyte+diff) MOD 256 650 STA rompoint 660 LDA #(lastbyte+diff) DIV 256 670 STA rompoint+1 680 LDA romnumber 690 EOR #&F 700 STA phrom 710 .exit 720 PLA 730 LDA #0 740 RTS 750 .fourteen 760 CMP #14 770 BNE out 780 LDA phrom 790 EOR #&F 800 CMP romnumber 810 BNE out 820 LDY #0 830 LDA (rompoint),Y 840 TAY 850 INC rompoint 860 BNE exit 870 INC rompoint+1 880 JMP exit+diff 890 .out 900 PLA 910 RTS 920 .language 930 CLI \ Enable interupt requests 940 LDX #&FF 950 TXS \ Reset stack 960 LDA #(basic+diff) MOD 256 970 STA breakv 980 LDA #(basic+diff) DIV 256 990 STA breakv+1 1000 LDA #&8D 1010 JSR osbyte \ *ROM 1020 LDA #&8B 1030 LDX #1 1040 LDY #0 1050 JSR osbyte \ *OPT1,0 1060 LDA #&0F 1070 LDX #0 1080 JSR osbyte \ Flush all buffers 1090 LDA #&FF 1100 PHA 1110 .keyboard 1120 PLA 1130 TAX 1140 INX 1150 TXA 1160 PHA 1170 LDY rfscomm+diff,X 1180 BEQ basic 1190 LDA #&8A 1200 LDX #0 1210 JSR osbyte 1220 JMP keyboard+diff 1230 .basic 1240 LDA #&BB 1250 LDX #0 1260 LDY #&FF 1270 JSR osbyte \ Find BASIC 1280 LDA #&8E 1290 JMP osbyte \ Enter BASIC 1300 .rfscomm 1310 OPT FNequs("CHAIN""DEMO""") 1320 OPT FNequb(&0D) 1330 BRK 1340 .lastbyte 1350 ] 1360 NEXT 1370 O%=lastbyte 1380 CHAIN"RFSGEN" 1390 DEFFNequb(byte) 1400 ?P%=byte 1410 P%=P%+1 1420 =pass 1430 DEFFNequw(word) 1440 ?P%=word MOD 256 1450 P%?1=word DIV 256 1460 P%=P%+2 1470 =pass 1480 DEFFNequd(double) 1490 !P%=double 1500 P%=P%+4 1510 =pass 1520 DEFFNequs(string$) 1530 $P%=string$ 1540 P%=P%+LEN(string$) 1550 =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 32 31 20 2d 20 52 46 53 20 6c |odule 21 - RFS l| 00000030 61 6e 67 75 61 67 65 20 72 6f 6d 0d 2d 2d 2d 2d |anguage rom.----| 00000040 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| * 00000070 2d 2d 2d 2d 2d 2d 2d 0d 0d 20 20 49 6e 20 4d 6f |-------.. In Mo| 00000080 64 75 6c 65 20 32 30 20 79 6f 75 20 77 65 72 65 |dule 20 you were| 00000090 20 73 68 6f 77 6e 20 6f 6e 65 20 77 61 79 20 69 | shown one way i| 000000a0 6e 20 77 68 69 63 68 20 70 72 6f 67 72 61 6d 73 |n which programs| 000000b0 20 73 74 6f 72 65 64 20 69 6e 20 74 68 65 0d 52 | stored in the.R| 000000c0 46 53 20 63 61 6e 20 62 65 20 72 75 6e 20 77 69 |FS can be run wi| 000000d0 74 68 20 2a 20 63 6f 6d 6d 61 6e 64 73 2e 20 54 |th * commands. T| 000000e0 68 65 20 70 72 6f 67 72 61 6d 73 20 75 73 65 64 |he programs used| 000000f0 20 74 6f 20 64 65 6d 6f 6e 73 74 72 61 74 65 20 | to demonstrate | 00000100 74 68 65 0d 74 65 63 68 6e 69 71 75 65 20 63 72 |the.technique cr| 00000110 65 61 74 65 64 20 61 20 73 65 72 76 69 63 65 20 |eated a service | 00000120 72 6f 6d 20 69 6d 61 67 65 2e 20 49 6e 20 74 68 |rom image. In th| 00000130 69 73 20 6d 6f 64 75 6c 65 20 49 20 77 69 6c 6c |is module I will| 00000140 20 73 68 6f 77 20 79 6f 75 0d 68 6f 77 20 61 20 | show you.how a | 00000150 6c 61 6e 67 75 61 67 65 20 72 6f 6d 20 64 65 73 |language rom des| 00000160 69 67 6e 20 63 61 6e 20 62 65 20 75 73 65 64 20 |ign can be used | 00000170 74 6f 20 61 63 68 69 65 76 65 20 61 20 73 69 6d |to achieve a sim| 00000180 69 6c 61 72 20 65 66 66 65 63 74 2e 0d 0d 20 20 |ilar effect... | 00000190 4f 6e 65 20 72 65 61 73 6f 6e 20 77 68 79 20 79 |One reason why y| 000001a0 6f 75 20 6d 69 67 68 74 20 63 68 6f 6f 73 65 20 |ou might choose | 000001b0 74 6f 20 69 6d 70 6c 65 6d 65 6e 74 20 61 6e 20 |to implement an | 000001c0 52 46 53 20 6c 61 6e 67 75 61 67 65 20 72 6f 6d |RFS language rom| 000001d0 20 69 73 0d 74 68 61 74 20 69 74 20 77 69 6c 6c | is.that it will| 000001e0 20 65 6e 61 62 6c 65 20 79 6f 75 20 74 6f 20 64 | enable you to d| 000001f0 65 73 69 67 6e 20 61 20 73 6f 20 63 61 6c 6c 65 |esign a so calle| 00000200 64 20 74 75 72 6e 6b 65 79 20 73 79 73 74 65 6d |d turnkey system| 00000210 20 61 73 20 77 65 6c 6c 0d 61 73 20 61 6c 6c 6f | as well.as allo| 00000220 77 20 79 6f 75 20 74 6f 20 72 75 6e 20 74 68 65 |w you to run the| 00000230 20 52 46 53 20 73 6f 66 74 77 61 72 65 20 77 69 | RFS software wi| 00000240 74 68 20 61 20 6e 65 77 20 2a 20 63 6f 6d 6d 61 |th a new * comma| 00000250 6e 64 2e 20 41 20 74 75 72 6e 6b 65 79 0d 63 6f |nd. A turnkey.co| 00000260 6d 70 75 74 65 72 20 73 79 73 74 65 6d 20 69 73 |mputer system is| 00000270 20 6f 6e 65 20 77 68 69 63 68 20 61 75 74 6f 6d | one which autom| 00000280 61 74 69 63 61 6c 6c 79 20 72 75 6e 73 20 63 75 |atically runs cu| 00000290 73 74 6f 6d 20 73 6f 66 74 77 61 72 65 20 77 68 |stom software wh| 000002a0 65 6e 0d 69 74 20 69 73 20 73 77 69 74 63 68 65 |en.it is switche| 000002b0 64 20 6f 6e 2e 0d 0d 20 20 49 66 20 79 6f 75 20 |d on... If you | 000002c0 68 61 76 65 20 61 20 6c 61 6e 67 75 61 67 65 20 |have a language | 000002d0 72 6f 6d 20 69 6e 20 73 6f 63 6b 65 74 20 26 30 |rom in socket &0| 000002e0 46 2c 20 6f 72 20 69 6e 20 61 20 62 61 74 74 65 |F, or in a batte| 000002f0 72 79 20 62 61 63 6b 65 64 2d 75 70 0d 73 69 64 |ry backed-up.sid| 00000300 65 77 61 79 73 20 72 61 6d 20 73 6f 63 6b 65 74 |eways ram socket| 00000310 20 26 30 46 2c 20 74 68 65 6e 20 74 68 61 74 20 | &0F, then that | 00000320 72 6f 6d 20 69 6d 61 67 65 20 77 69 6c 6c 20 62 |rom image will b| 00000330 65 20 62 6f 6f 74 65 64 20 77 68 65 6e 20 74 68 |e booted when th| 00000340 65 0d 63 6f 6d 70 75 74 65 72 20 69 73 20 73 77 |e.computer is sw| 00000350 69 74 63 68 65 64 20 6f 6e 20 61 6e 64 20 77 68 |itched on and wh| 00000360 65 6e 20 43 74 72 6c 2b 42 72 65 61 6b 20 69 73 |en Ctrl+Break is| 00000370 20 70 72 65 73 73 65 64 2e 20 54 68 69 73 20 69 | pressed. This i| 00000380 73 20 74 72 75 65 0d 66 6f 72 20 61 6c 6c 20 6c |s true.for all l| 00000390 61 6e 67 75 61 67 65 20 72 6f 6d 73 20 69 6e 20 |anguage roms in | 000003a0 74 68 65 20 68 69 67 68 65 73 74 20 70 72 69 6f |the highest prio| 000003b0 72 69 74 79 20 72 6f 6d 20 73 6f 63 6b 65 74 20 |rity rom socket | 000003c0 62 75 74 2c 20 69 66 20 79 6f 75 72 0d 63 75 73 |but, if your.cus| 000003d0 74 6f 6d 20 73 6f 66 74 77 61 72 65 20 69 73 20 |tom software is | 000003e0 77 72 69 74 74 65 6e 20 69 6e 20 42 41 53 49 43 |written in BASIC| 000003f0 2c 20 79 6f 75 20 77 6f 75 6c 64 20 6e 6f 72 6d |, you would norm| 00000400 61 6c 6c 79 20 68 61 76 65 20 74 6f 0d 72 65 2d |ally have to.re-| 00000410 77 72 69 74 65 20 79 6f 75 72 20 70 72 6f 67 72 |write your progr| 00000420 61 6d 20 61 73 20 61 6e 20 69 6e 64 65 70 65 6e |am as an indepen| 00000430 64 61 6e 74 20 6d 61 63 68 69 6e 65 20 63 6f 64 |dant machine cod| 00000440 65 20 6c 61 6e 67 75 61 67 65 20 74 6f 20 72 75 |e language to ru| 00000450 6e 0d 69 74 20 69 6e 20 74 68 69 73 20 77 61 79 |n.it in this way| 00000460 2e 20 55 73 69 6e 67 20 61 6e 20 52 46 53 20 6c |. Using an RFS l| 00000470 61 6e 67 75 61 67 65 20 72 6f 6d 20 77 69 6c 6c |anguage rom will| 00000480 20 61 6c 6c 6f 77 20 79 6f 75 20 74 6f 20 75 73 | allow you to us| 00000490 65 20 79 6f 75 72 0d 73 6f 66 74 77 61 72 65 20 |e your.software | 000004a0 69 6e 20 61 20 74 75 72 6e 6b 65 79 20 73 79 73 |in a turnkey sys| 000004b0 74 65 6d 20 77 69 74 68 6f 75 74 20 74 72 61 6e |tem without tran| 000004c0 73 6c 61 74 69 6e 67 20 69 74 20 69 6e 74 6f 20 |slating it into | 000004d0 61 6e 0d 69 6e 64 65 70 65 6e 64 61 6e 74 20 6d |an.independant m| 000004e0 61 63 68 69 6e 65 20 63 6f 64 65 20 70 72 6f 67 |achine code prog| 000004f0 72 61 6d 2e 0d 0d 20 20 41 6e 20 52 46 53 20 6c |ram... An RFS l| 00000500 61 6e 67 75 61 67 65 20 72 6f 6d 20 63 61 6e 20 |anguage rom can | 00000510 62 65 20 75 73 65 64 20 69 6e 20 73 6f 63 6b 65 |be used in socke| 00000520 74 20 26 30 46 20 6f 66 20 74 68 65 20 42 42 43 |t &0F of the BBC| 00000530 20 42 20 73 69 6d 70 6c 79 20 62 79 0d 6d 6f 76 | B simply by.mov| 00000540 69 6e 67 20 74 68 65 20 6f 74 68 65 72 20 72 6f |ing the other ro| 00000550 6d 20 63 68 69 70 73 20 74 6f 20 6d 61 6b 65 20 |m chips to make | 00000560 72 6f 6f 6d 20 66 6f 72 20 69 74 2e 20 4f 6e 20 |room for it. On | 00000570 74 68 65 20 42 42 43 20 42 2b 20 69 74 20 69 73 |the BBC B+ it is| 00000580 0d 6e 65 63 65 73 73 61 72 79 20 74 6f 20 61 6c |.necessary to al| 00000590 74 65 72 20 6c 69 6e 6b 20 53 31 33 20 28 74 6f |ter link S13 (to| 000005a0 20 74 68 65 20 72 69 67 68 74 20 6f 66 20 49 43 | the right of IC| 000005b0 34 36 29 20 74 6f 20 67 69 76 65 20 74 68 65 20 |46) to give the | 000005c0 68 69 67 68 65 73 74 0d 70 72 69 6f 72 69 74 79 |highest.priority| 000005d0 20 72 6f 6d 20 73 6f 63 6b 65 74 20 6f 6e 20 74 | rom socket on t| 000005e0 68 65 20 63 69 72 63 75 69 74 20 62 6f 61 72 64 |he circuit board| 000005f0 20 70 72 69 6f 72 69 74 79 20 6f 76 65 72 20 42 | priority over B| 00000600 41 53 49 43 2e 20 54 68 65 20 52 46 53 0d 6c 61 |ASIC. The RFS.la| 00000610 6e 67 75 61 67 65 20 72 6f 6d 20 69 6d 61 67 65 |nguage rom image| 00000620 20 63 61 6e 20 62 65 20 63 6f 6e 66 69 67 75 72 | can be configur| 00000630 65 64 20 61 73 20 74 68 65 20 73 74 61 72 74 20 |ed as the start | 00000640 75 70 20 6c 61 6e 67 75 61 67 65 20 6f 6e 20 74 |up language on t| 00000650 68 65 0d 4d 61 73 74 65 72 20 62 79 20 75 73 69 |he.Master by usi| 00000660 6e 67 20 74 68 65 20 2a 43 4f 4e 46 49 47 55 52 |ng the *CONFIGUR| 00000670 45 20 4c 41 4e 47 20 3c 72 6f 6d 20 6e 75 6d 62 |E LANG <rom numb| 00000680 65 72 3e 20 63 6f 6d 6d 61 6e 64 2e 0d 0d 20 20 |er> command... | 00000690 54 68 65 20 52 46 53 20 6c 61 6e 67 75 61 67 65 |The RFS language| 000006a0 20 72 6f 6d 20 63 61 6e 20 61 6c 73 6f 20 62 65 | rom can also be| 000006b0 20 75 73 65 64 20 69 6e 20 61 20 6c 6f 77 65 72 | used in a lower| 000006c0 20 70 72 69 6f 72 69 74 79 20 73 6f 63 6b 65 74 | priority socket| 000006d0 0d 74 68 61 6e 20 42 41 53 49 43 20 77 68 65 6e |.than BASIC when| 000006e0 20 69 74 20 77 69 6c 6c 20 66 75 6e 63 74 69 6f | it will functio| 000006f0 6e 20 6c 69 6b 65 20 61 6e 79 20 6f 74 68 65 72 |n like any other| 00000700 20 6c 61 6e 67 75 61 67 65 20 72 6f 6d 20 61 6e | language rom an| 00000710 64 20 69 74 0d 77 69 6c 6c 20 62 65 20 73 65 6c |d it.will be sel| 00000720 65 63 74 65 64 20 77 68 65 6e 20 63 61 6c 6c 65 |ected when calle| 00000730 64 20 77 69 74 68 20 2a 46 58 31 34 32 2c 6e 20 |d with *FX142,n | 00000740 6f 72 20 69 74 73 20 2a 20 63 6f 6d 6d 61 6e 64 |or its * command| 00000750 2e 0d 0d 20 20 49 6e 20 74 68 65 20 70 72 6f 67 |... In the prog| 00000760 72 61 6d 20 52 46 53 45 52 56 20 74 68 65 20 69 |ram RFSERV the i| 00000770 6e 74 65 72 70 72 65 74 65 72 20 70 61 73 73 65 |nterpreter passe| 00000780 64 20 63 6f 6e 74 72 6f 6c 20 74 6f 20 61 20 73 |d control to a s| 00000790 65 72 76 69 63 65 0d 72 6f 75 74 69 6e 65 20 77 |ervice.routine w| 000007a0 68 69 63 68 20 73 65 6c 65 63 74 65 64 20 74 68 |hich selected th| 000007b0 65 20 52 46 53 2c 20 73 74 6f 72 65 64 20 61 20 |e RFS, stored a | 000007c0 43 68 61 69 6e 20 63 6f 6d 6d 61 6e 64 20 69 6e |Chain command in| 000007d0 20 74 68 65 20 6b 65 79 62 6f 61 72 64 0d 62 75 | the keyboard.bu| 000007e0 66 66 65 72 2c 20 61 6e 64 20 74 68 65 6e 20 65 |ffer, and then e| 000007f0 6e 74 65 72 65 64 20 42 41 53 49 43 20 77 68 69 |ntered BASIC whi| 00000800 63 68 20 65 78 65 63 75 74 65 64 20 74 68 65 20 |ch executed the | 00000810 63 6f 6d 6d 61 6e 64 20 69 6e 20 74 68 65 0d 6b |command in the.k| 00000820 65 79 62 6f 61 72 64 20 62 75 66 66 65 72 2e 20 |eyboard buffer. | 00000830 54 68 65 20 70 72 6f 67 72 61 6d 20 52 46 53 4c |The program RFSL| 00000840 41 4e 47 20 61 63 68 69 65 76 65 73 20 74 68 65 |ANG achieves the| 00000850 20 73 61 6d 65 20 72 65 73 75 6c 74 20 62 79 0d | same result by.| 00000860 65 6e 74 65 72 69 6e 67 20 61 20 6c 61 6e 67 75 |entering a langu| 00000870 61 67 65 20 77 68 69 63 68 20 65 76 65 6e 74 75 |age which eventu| 00000880 61 6c 6c 79 20 65 78 65 63 75 74 65 73 20 74 68 |ally executes th| 00000890 65 20 73 61 6d 65 20 63 6f 64 69 6e 67 20 75 73 |e same coding us| 000008a0 65 64 20 62 79 0d 74 68 65 20 73 65 72 76 69 63 |ed by.the servic| 000008b0 65 20 72 6f 75 74 69 6e 65 20 69 6e 20 52 46 53 |e routine in RFS| 000008c0 45 52 56 2e 0d 0d 20 20 54 68 65 20 6f 6e 65 20 |ERV... The one | 000008d0 63 6f 6d 6d 61 6e 64 20 69 6e 74 65 72 70 72 65 |command interpre| 000008e0 74 65 72 20 69 73 20 75 73 65 64 20 69 6e 20 74 |ter is used in t| 000008f0 68 65 20 70 72 6f 67 72 61 6d 20 52 46 53 4c 41 |he program RFSLA| 00000900 4e 47 20 74 6f 0d 63 6f 6d 70 61 72 65 20 61 6e |NG to.compare an| 00000910 20 75 6e 72 65 63 6f 67 6e 69 73 65 64 20 63 6f | unrecognised co| 00000920 6d 6d 61 6e 64 20 77 69 74 68 20 74 68 65 20 74 |mmand with the t| 00000930 69 74 6c 65 20 73 74 72 69 6e 67 20 6f 66 20 74 |itle string of t| 00000940 68 65 20 72 6f 6d 2e 20 49 66 20 61 0d 6d 61 74 |he rom. If a.mat| 00000950 63 68 20 69 73 20 66 6f 75 6e 64 20 74 68 65 20 |ch is found the | 00000960 72 6f 6d 20 75 73 65 73 20 4f 73 62 79 74 65 20 |rom uses Osbyte | 00000970 26 38 45 20 74 6f 20 65 6e 74 65 72 20 74 68 65 |&8E to enter the| 00000980 20 72 6f 6d 20 61 74 20 69 74 73 0d 6c 61 6e 67 | rom at its.lang| 00000990 75 61 67 65 20 65 6e 74 72 79 20 70 6f 69 6e 74 |uage entry point| 000009a0 2e 20 57 68 65 6e 20 74 68 65 20 72 6f 6d 20 69 |. When the rom i| 000009b0 73 20 65 6e 74 65 72 65 64 20 61 74 20 69 74 73 |s entered at its| 000009c0 20 6c 61 6e 67 75 61 67 65 20 65 6e 74 72 79 0d | language entry.| 000009d0 70 6f 69 6e 74 20 69 74 20 6d 75 73 74 20 66 69 |point it must fi| 000009e0 72 73 74 20 65 6e 61 62 6c 65 20 69 6e 74 65 72 |rst enable inter| 000009f0 75 70 74 73 2c 20 72 65 73 65 74 20 74 68 65 20 |upts, reset the | 00000a00 73 74 61 63 6b 2c 20 61 6e 64 20 72 65 2d 76 65 |stack, and re-ve| 00000a10 63 74 6f 72 0d 74 68 65 20 62 72 65 61 6b 20 76 |ctor.the break v| 00000a20 65 63 74 6f 72 20 74 6f 20 70 6f 69 6e 74 20 74 |ector to point t| 00000a30 6f 20 61 6e 20 65 72 72 6f 72 20 68 61 6e 64 6c |o an error handl| 00000a40 69 6e 67 20 72 6f 75 74 69 6e 65 20 28 73 65 65 |ing routine (see| 00000a50 20 6d 6f 64 75 6c 65 0d 31 37 29 2e 20 54 68 65 | module.17). The| 00000a60 20 63 6f 6d 70 6c 65 74 65 20 6c 61 6e 67 75 61 | complete langua| 00000a70 67 65 20 63 6f 64 69 6e 67 20 66 72 6f 6d 20 52 |ge coding from R| 00000a80 46 53 4c 41 4e 47 20 69 73 20 73 68 6f 77 6e 20 |FSLANG is shown | 00000a90 69 6e 20 66 69 67 75 72 65 20 32 31 2e 31 0d 0d |in figure 21.1..| 00000aa0 0d 0d 0d 0d 2e 6c 61 6e 67 75 61 67 65 0d 20 20 |.....language. | 00000ab0 20 20 20 20 20 20 43 4c 49 20 20 20 20 20 20 20 | CLI | 00000ac0 20 20 20 20 20 20 20 20 20 20 20 5c 20 65 6e 61 | \ ena| 00000ad0 62 6c 65 20 69 6e 74 65 72 75 70 74 20 72 65 71 |ble interupt req| 00000ae0 75 65 73 74 73 0d 20 20 20 20 20 20 20 20 4c 44 |uests. LD| 00000af0 58 20 23 26 46 46 0d 20 20 20 20 20 20 20 20 54 |X #&FF. T| 00000b00 58 53 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |XS | 00000b10 20 20 20 20 5c 20 72 65 73 65 74 20 73 74 61 63 | \ reset stac| 00000b20 6b 0d 20 20 20 20 20 20 20 20 4c 44 41 20 23 62 |k. LDA #b| 00000b30 61 73 69 63 20 4d 4f 44 20 32 35 36 20 20 20 5c |asic MOD 256 \| 00000b40 20 6c 6f 77 20 62 79 74 65 20 6f 66 20 65 6e 74 | low byte of ent| 00000b50 65 72 20 42 41 53 49 43 20 61 64 64 72 65 73 73 |er BASIC address| 00000b60 0d 20 20 20 20 20 20 20 20 53 54 41 20 26 32 30 |. STA &20| 00000b70 32 20 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 |2 \ | 00000b80 73 74 6f 72 65 20 69 6e 20 42 72 65 61 6b 20 76 |store in Break v| 00000b90 65 63 74 6f 72 20 6c 6f 77 20 62 79 74 65 0d 20 |ector low byte. | 00000ba0 20 20 20 20 20 20 20 4c 44 41 20 23 62 61 73 69 | LDA #basi| 00000bb0 63 20 44 49 56 20 32 35 36 20 20 20 5c 20 68 69 |c DIV 256 \ hi| 00000bc0 67 68 20 62 79 74 65 20 6f 66 20 65 6e 74 65 72 |gh byte of enter| 00000bd0 20 42 41 53 49 43 20 61 64 64 72 65 73 73 0d 20 | BASIC address. | 00000be0 20 20 20 20 20 20 20 53 54 41 20 26 32 30 33 20 | STA &203 | 00000bf0 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 73 74 | \ st| 00000c00 6f 72 65 20 69 6e 20 42 72 65 61 6b 20 76 65 63 |ore in Break vec| 00000c10 74 6f 72 20 68 69 67 68 20 62 79 74 65 0d 20 20 |tor high byte. | 00000c20 20 20 20 20 20 20 4c 44 41 20 23 26 38 44 20 20 | LDA #&8D | 00000c30 20 20 20 20 20 20 20 20 20 20 20 5c 20 4f 73 62 | \ Osb| 00000c40 79 74 65 20 26 38 44 0d 20 20 20 20 20 20 20 20 |yte &8D. | 00000c50 4a 53 52 20 26 46 46 46 34 20 20 20 20 20 20 20 |JSR &FFF4 | 00000c60 20 20 20 20 20 5c 20 2a 52 4f 4d 0d 20 20 20 20 | \ *ROM. | 00000c70 20 20 20 20 4c 44 41 20 23 26 38 42 20 20 20 20 | LDA #&8B | 00000c80 20 20 20 20 20 20 20 20 20 5c 20 4f 73 62 79 74 | \ Osbyt| 00000c90 65 20 26 38 42 0d 20 20 20 20 20 20 20 20 4c 44 |e &8B. LD| 00000ca0 58 20 23 31 0d 20 20 20 20 20 20 20 20 4c 44 59 |X #1. LDY| 00000cb0 20 23 30 0d 20 20 20 20 20 20 20 20 4a 53 52 20 | #0. JSR | 00000cc0 26 46 46 46 34 20 20 20 20 20 20 20 20 20 20 20 |&FFF4 | 00000cd0 20 5c 20 2a 4f 50 54 20 31 2c 30 0d 20 20 20 20 | \ *OPT 1,0. | 00000ce0 20 20 20 20 4c 44 41 20 23 26 30 46 20 20 20 20 | LDA #&0F | 00000cf0 20 20 20 20 20 20 20 20 20 5c 20 4f 73 62 79 74 | \ Osbyt| 00000d00 65 20 26 30 46 0d 20 20 20 20 20 20 20 20 4c 44 |e &0F. LD| 00000d10 58 20 23 30 0d 20 20 20 20 20 20 20 20 4a 53 52 |X #0. JSR| 00000d20 20 26 46 46 46 34 20 20 20 20 20 20 20 20 20 20 | &FFF4 | 00000d30 20 20 5c 20 66 6c 75 73 68 20 61 6c 6c 20 62 75 | \ flush all bu| 00000d40 66 66 65 72 73 0d 20 20 20 20 20 20 20 20 4c 44 |ffers. LD| 00000d50 41 20 23 26 46 46 20 20 20 20 20 20 20 20 20 20 |A #&FF | 00000d60 20 20 20 5c 20 69 6e 69 74 69 61 6c 69 73 65 20 | \ initialise | 00000d70 6f 66 66 73 65 74 0d 20 20 20 20 20 20 20 20 50 |offset. P| 00000d80 48 41 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |HA | 00000d90 20 20 20 20 5c 20 73 74 6f 72 65 20 6f 66 66 73 | \ store offs| 00000da0 65 74 0d 2e 6b 65 79 62 6f 61 72 64 0d 20 20 20 |et..keyboard. | 00000db0 20 20 20 20 20 50 4c 41 20 20 20 20 20 20 20 20 | PLA | 00000dc0 20 20 20 20 20 20 20 20 20 20 5c 20 72 65 73 74 | \ rest| 00000dd0 6f 72 65 20 6f 66 66 73 65 74 0d 20 20 20 20 20 |ore offset. | 00000de0 20 20 20 54 41 58 20 20 20 20 20 20 20 20 20 20 | TAX | 00000df0 20 20 20 20 20 20 20 20 5c 20 74 72 61 6e 73 66 | \ transf| 00000e00 65 72 20 6f 66 66 73 65 74 20 74 6f 20 58 0d 20 |er offset to X. | 00000e10 20 20 20 20 20 20 20 49 4e 58 20 20 20 20 20 20 | INX | 00000e20 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 69 6e | \ in| 00000e30 63 72 65 6d 65 6e 74 20 6f 66 66 73 65 74 0d 20 |crement offset. | 00000e40 20 20 20 20 20 20 20 54 58 41 20 20 20 20 20 20 | TXA | 00000e50 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 63 6f | \ co| 00000e60 70 79 20 6f 66 66 73 65 74 20 74 6f 20 41 0d 20 |py offset to A. | 00000e70 20 20 20 20 20 20 20 50 48 41 20 20 20 20 20 20 | PHA | 00000e80 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 73 74 | \ st| 00000e90 6f 72 65 20 6f 66 66 73 65 74 0d 20 20 20 20 20 |ore offset. | 00000ea0 20 20 20 4c 44 59 20 72 66 73 63 6f 6d 6d 2c 58 | LDY rfscomm,X| 00000eb0 20 20 20 20 20 20 20 20 5c 20 6c 6f 61 64 20 63 | \ load c| 00000ec0 68 61 72 61 63 74 65 72 0d 20 20 20 20 20 20 20 |haracter. | 00000ed0 20 42 45 51 20 62 61 73 69 63 20 20 20 20 20 20 | BEQ basic | 00000ee0 20 20 20 20 20 20 5c 20 62 72 61 6e 63 68 20 69 | \ branch i| 00000ef0 66 20 65 6e 64 20 6f 66 20 74 65 78 74 20 63 68 |f end of text ch| 00000f00 61 72 61 63 74 65 72 0d 20 20 20 20 20 20 20 20 |aracter. | 00000f10 4c 44 41 20 23 26 38 41 20 20 20 20 20 20 20 20 |LDA #&8A | 00000f20 20 20 20 20 20 5c 20 4f 73 62 79 74 65 20 26 38 | \ Osbyte &8| 00000f30 41 0d 20 20 20 20 20 20 20 20 4c 44 58 20 23 30 |A. LDX #0| 00000f40 0d 20 20 20 20 20 20 20 20 4a 53 52 20 26 46 46 |. JSR &FF| 00000f50 46 34 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 |F4 \ | 00000f60 63 68 61 72 61 63 74 65 72 20 69 6e 74 6f 20 6b |character into k| 00000f70 65 79 62 6f 61 72 64 20 62 75 66 66 65 72 0d 20 |eyboard buffer. | 00000f80 20 20 20 20 20 20 20 4a 4d 50 20 6b 65 79 62 6f | JMP keybo| 00000f90 61 72 64 20 20 20 20 20 20 20 20 20 5c 20 67 6f |ard \ go| 00000fa0 20 66 6f 72 20 6e 65 78 74 20 63 68 61 72 61 63 | for next charac| 00000fb0 74 65 72 0d 2e 62 61 73 69 63 0d 20 20 20 20 20 |ter..basic. | 00000fc0 20 20 20 4c 44 41 20 23 26 42 42 20 20 20 20 20 | LDA #&BB | 00000fd0 20 20 20 20 20 20 20 20 5c 20 4f 73 62 79 74 65 | \ Osbyte| 00000fe0 20 26 42 42 0d 20 20 20 20 20 20 20 20 4c 44 58 | &BB. LDX| 00000ff0 20 23 30 0d 20 20 20 20 20 20 20 20 4c 44 59 20 | #0. LDY | 00001000 23 26 46 46 0d 20 20 20 20 20 20 20 20 4a 53 52 |#&FF. JSR| 00001010 20 26 46 46 46 34 20 20 20 20 20 20 20 20 20 20 | &FFF4 | 00001020 20 20 5c 20 66 69 6e 64 20 42 41 53 49 43 0d 20 | \ find BASIC. | 00001030 20 20 20 20 20 20 20 4c 44 41 20 23 26 38 45 20 | LDA #&8E | 00001040 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 4f 73 | \ Os| 00001050 62 79 74 65 20 26 38 45 0d 20 20 20 20 20 20 20 |byte &8E. | 00001060 20 4a 4d 50 20 26 46 46 46 34 20 20 20 20 20 20 | JMP &FFF4 | 00001070 20 20 20 20 20 20 5c 20 65 6e 74 65 72 20 42 41 | \ enter BA| 00001080 53 49 43 20 6e 6f 20 72 65 74 75 72 6e 0d 20 20 |SIC no return. | 00001090 20 20 20 20 20 20 20 2e 0d 20 20 20 20 20 20 20 | .. | 000010a0 20 20 2e 0d 20 20 20 20 20 20 20 20 20 2e 0d 2e | .. ...| 000010b0 72 66 73 63 6f 6d 6d 0d 20 20 20 20 20 20 20 20 |rfscomm. | 000010c0 45 51 55 53 20 22 43 48 41 49 4e 22 22 44 45 4d |EQUS "CHAIN""DEM| 000010d0 4f 22 22 22 20 5c 20 63 68 61 69 6e 20 63 6f 6d |O""" \ chain com| 000010e0 6d 61 6e 64 20 66 6f 72 20 42 41 53 49 43 0d 20 |mand for BASIC. | 000010f0 20 20 20 20 20 20 20 45 51 55 42 20 26 30 44 20 | EQUB &0D | 00001100 20 20 20 20 20 20 20 20 20 20 20 20 5c 20 3c 52 | \ <R| 00001110 65 74 75 72 6e 3e 0d 20 20 20 20 20 20 20 20 42 |eturn>. B| 00001120 52 4b 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |RK | 00001130 20 20 20 20 5c 20 65 6e 64 20 6f 66 20 74 65 78 | \ end of tex| 00001140 74 20 6d 61 72 6b 65 72 0d 0d 46 69 67 75 72 65 |t marker..Figure| 00001150 20 32 31 2e 31 20 20 54 68 65 20 6c 61 6e 67 75 | 21.1 The langu| 00001160 61 67 65 20 63 6f 64 69 6e 67 20 66 72 6f 6d 20 |age coding from | 00001170 52 46 53 4c 41 4e 47 2e 0d 2d 2d 2d 2d 2d 2d 2d |RFSLANG..-------| 00001180 2d 2d 2d 2d 20 20 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |---- ----------| 00001190 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------| 000011a0 2d 2d 2d 2d 2d 2d 2d 0d 0d 0d 0d 20 20 54 68 65 |-------.... The| 000011b0 20 62 72 65 61 6b 20 76 65 63 74 6f 72 20 69 6e | break vector in| 000011c0 20 52 46 53 4c 41 4e 47 20 70 6f 69 6e 74 73 20 | RFSLANG points | 000011d0 74 6f 20 74 68 65 20 63 6f 64 65 20 77 68 69 63 |to the code whic| 000011e0 68 20 66 69 6e 64 73 20 61 6e 64 0d 65 6e 74 65 |h finds and.ente| 000011f0 72 73 20 42 41 53 49 43 20 73 6f 20 74 68 61 74 |rs BASIC so that| 00001200 2c 20 69 66 20 61 6e 20 65 72 72 6f 72 20 69 73 |, if an error is| 00001210 20 67 65 6e 65 72 61 74 65 64 20 77 68 69 6c 65 | generated while| 00001220 20 74 68 65 20 6c 61 6e 67 75 61 67 65 20 69 73 | the language is| 00001230 0d 61 63 74 69 76 65 2c 20 69 74 20 72 65 73 70 |.active, it resp| 00001240 6f 6e 64 73 20 62 79 20 65 6e 74 65 72 69 6e 67 |onds by entering| 00001250 20 42 41 53 49 43 2e 20 54 68 65 20 6c 61 6e 67 | BASIC. The lang| 00001260 75 61 67 65 20 64 65 66 69 6e 65 64 20 62 79 20 |uage defined by | 00001270 52 46 53 4c 41 4e 47 0d 77 69 6c 6c 20 6f 6e 6c |RFSLANG.will onl| 00001280 79 20 65 76 65 72 20 62 65 20 61 63 74 69 76 65 |y ever be active| 00001290 20 66 6f 72 20 61 20 66 65 77 20 6d 69 6c 6c 69 | for a few milli| 000012a0 2d 73 65 63 6f 6e 64 73 20 62 65 66 6f 72 65 20 |-seconds before | 000012b0 69 74 20 73 65 6c 65 63 74 73 0d 42 41 53 49 43 |it selects.BASIC| 000012c0 20 74 6f 20 72 65 70 6c 61 63 65 20 69 74 20 61 | to replace it a| 000012d0 6e 64 20 67 65 6e 65 72 61 74 69 6e 67 20 61 6e |nd generating an| 000012e0 20 65 72 72 6f 72 20 69 73 20 71 75 69 74 65 20 | error is quite | 000012f0 75 6e 6c 69 6b 65 6c 79 2e 20 49 20 68 61 76 65 |unlikely. I have| 00001300 0d 62 65 65 6e 20 75 6e 61 62 6c 65 20 74 6f 20 |.been unable to | 00001310 67 65 6e 65 72 61 74 65 20 61 6e 20 65 72 72 6f |generate an erro| 00001320 72 20 77 69 74 68 69 6e 20 74 68 65 20 6c 61 6e |r within the lan| 00001330 67 75 61 67 65 20 77 68 65 6e 20 74 65 73 74 69 |guage when testi| 00001340 6e 67 20 74 68 65 0d 70 72 6f 67 72 61 6d 2e 20 |ng the.program. | 00001350 54 68 69 73 20 73 68 6f 72 74 20 63 75 74 20 6d |This short cut m| 00001360 65 74 68 6f 64 20 6f 66 20 64 65 61 6c 69 6e 67 |ethod of dealing| 00001370 20 77 69 74 68 20 65 72 72 6f 72 73 20 62 79 20 | with errors by | 00001380 69 67 6e 6f 72 69 6e 67 20 74 68 65 6d 0d 6d 65 |ignoring them.me| 00001390 61 6e 73 20 74 68 61 74 20 74 68 65 20 72 6f 6d |ans that the rom| 000013a0 20 77 69 6c 6c 20 6e 65 65 64 20 74 6f 20 62 65 | will need to be| 000013b0 20 72 65 2d 62 6f 6f 74 65 64 20 69 66 20 74 68 | re-booted if th| 000013c0 65 79 20 6f 63 63 75 72 2e 0d 0d 20 20 41 66 74 |ey occur... Aft| 000013d0 65 72 20 69 6e 69 74 69 61 6c 69 73 69 6e 67 20 |er initialising | 000013e0 74 68 65 20 6c 61 6e 67 75 61 67 65 20 74 68 65 |the language the| 000013f0 20 63 6f 64 69 6e 67 20 64 6f 65 73 20 74 68 65 | coding does the| 00001400 20 73 61 6d 65 20 6a 6f 62 20 61 73 20 74 68 65 | same job as the| 00001410 0d 73 65 72 76 69 63 65 20 72 6f 75 74 69 6e 65 |.service routine| 00001420 20 69 6e 20 52 46 53 45 52 56 2e 20 49 74 20 73 | in RFSERV. It s| 00001430 65 6c 65 63 74 73 20 74 68 65 20 52 46 53 2c 20 |elects the RFS, | 00001440 69 6e 73 65 72 74 73 20 74 68 65 20 43 68 61 69 |inserts the Chai| 00001450 6e 0d 63 6f 6d 6d 61 6e 64 20 69 6e 74 6f 20 74 |n.command into t| 00001460 68 65 20 6b 65 79 62 6f 61 72 64 20 62 75 66 66 |he keyboard buff| 00001470 65 72 2c 20 61 6e 64 20 66 69 6e 64 73 20 61 6e |er, and finds an| 00001480 64 20 65 6e 74 65 72 73 20 42 41 53 49 43 2e 20 |d enters BASIC. | 00001490 57 68 65 6e 0d 42 41 53 49 43 20 69 73 20 65 6e |When.BASIC is en| 000014a0 74 65 72 65 64 20 69 6e 20 74 68 69 73 20 77 61 |tered in this wa| 000014b0 79 20 69 74 20 65 78 65 63 75 74 65 73 20 74 68 |y it executes th| 000014c0 65 20 63 6f 6d 6d 61 6e 64 20 69 6e 20 74 68 65 |e command in the| 000014d0 20 6b 65 79 62 6f 61 72 64 0d 62 75 66 66 65 72 | keyboard.buffer| 000014e0 20 61 6e 64 20 63 68 61 69 6e 73 20 74 68 65 20 | and chains the | 000014f0 66 69 6c 65 20 66 72 6f 6d 20 74 68 65 20 52 46 |file from the RF| 00001500 53 2e 0d 0d 20 20 54 68 65 20 70 72 6f 67 72 61 |S... The progra| 00001510 6d 20 52 46 53 4c 41 4e 47 20 6d 75 73 74 20 62 |m RFSLANG must b| 00001520 65 20 75 73 65 64 20 77 69 74 68 20 74 68 65 20 |e used with the | 00001530 66 6f 72 6d 61 74 74 69 6e 67 20 70 72 6f 67 72 |formatting progr| 00001540 61 6d 20 52 46 53 47 45 4e 0d 61 6e 64 20 77 68 |am RFSGEN.and wh| 00001550 61 74 65 76 65 72 20 70 72 6f 67 72 61 6d 73 20 |atever programs | 00001560 79 6f 75 20 77 61 6e 74 20 74 6f 20 73 74 6f 72 |you want to stor| 00001570 65 20 69 6e 20 74 68 65 20 52 46 53 2e 20 54 68 |e in the RFS. Th| 00001580 65 73 65 20 70 72 6f 67 72 61 6d 73 20 61 72 65 |ese programs are| 00001590 0d 75 73 65 64 20 74 6f 20 63 72 65 61 74 65 20 |.used to create | 000015a0 74 68 65 20 52 46 53 20 72 6f 6d 20 69 6d 61 67 |the RFS rom imag| 000015b0 65 20 61 6e 64 20 64 65 74 61 69 6c 65 64 20 69 |e and detailed i| 000015c0 6e 73 74 72 75 63 74 69 6f 6e 73 20 6f 6e 20 75 |nstructions on u| 000015d0 73 69 6e 67 0d 74 68 65 6d 20 77 65 72 65 20 69 |sing.them were i| 000015e0 6e 63 6c 75 64 65 64 20 69 6e 20 4d 6f 64 75 6c |ncluded in Modul| 000015f0 65 20 31 38 2e 20 52 46 53 4c 41 4e 47 20 77 61 |e 18. RFSLANG wa| 00001600 73 20 77 72 69 74 74 65 6e 20 74 6f 20 62 65 20 |s written to be | 00001610 75 73 65 64 20 77 69 74 68 0d 74 68 65 20 73 75 |used with.the su| 00001620 70 70 6c 69 65 64 20 64 65 6d 6f 6e 73 74 72 61 |pplied demonstra| 00001630 74 69 6f 6e 20 70 72 6f 67 72 61 6d 20 44 45 4d |tion program DEM| 00001640 4f 2e 20 49 66 20 79 6f 75 20 77 61 6e 74 20 74 |O. If you want t| 00001650 6f 20 75 73 65 20 69 74 20 77 69 74 68 0d 61 6e |o use it with.an| 00001660 79 20 6f 74 68 65 72 20 70 72 6f 67 72 61 6d 20 |y other program | 00001670 79 6f 75 20 77 69 6c 6c 20 6e 65 65 64 20 74 6f |you will need to| 00001680 20 61 6c 74 65 72 20 74 68 65 20 63 6f 6d 6d 61 | alter the comma| 00001690 6e 64 20 73 74 72 69 6e 67 20 69 6e 20 6c 69 6e |nd string in lin| 000016a0 65 73 0d 31 33 31 30 20 74 6f 20 31 33 33 30 2e |es.1310 to 1330.| 000016b0 20 59 6f 75 20 63 61 6e 20 61 6c 73 6f 20 61 6c | You can also al| 000016c0 74 65 72 20 74 68 65 20 72 6f 6d 20 74 69 74 6c |ter the rom titl| 000016d0 65 20 73 74 72 69 6e 67 20 69 6e 20 6c 69 6e 65 |e string in line| 000016e0 20 32 32 30 20 69 66 0d 79 6f 75 20 77 6f 75 6c | 220 if.you woul| 000016f0 64 20 70 72 65 66 65 72 20 74 6f 20 73 65 6c 65 |d prefer to sele| 00001700 63 74 20 74 68 65 20 6c 61 6e 67 75 61 67 65 20 |ct the language | 00001710 77 69 74 68 20 61 20 63 6f 6d 6d 61 6e 64 20 6f |with a command o| 00001720 74 68 65 72 20 74 68 61 6e 0d 2a 52 46 53 2e 0d |ther than.*RFS..| 00001730 0d 0d 0d 0d 20 20 20 31 30 20 52 45 4d 3a 20 52 |.... 10 REM: R| 00001740 46 53 4c 41 4e 47 0d 20 20 20 32 30 20 4d 4f 44 |FSLANG. 20 MOD| 00001750 45 37 0d 20 20 20 33 30 20 48 49 4d 45 4d 3d 26 |E7. 30 HIMEM=&| 00001760 33 43 30 30 0d 20 20 20 34 30 20 64 69 66 66 3d |3C00. 40 diff=| 00001770 26 38 30 30 30 2d 48 49 4d 45 4d 0d 20 20 20 35 |&8000-HIMEM. 5| 00001780 30 20 48 25 3d 48 49 4d 45 4d 0d 20 20 20 36 30 |0 H%=HIMEM. 60| 00001790 20 63 6f 6d 76 65 63 3d 26 46 32 0d 20 20 20 37 | comvec=&F2. 7| 000017a0 30 20 72 6f 6d 6e 75 6d 62 65 72 3d 26 46 34 0d |0 romnumber=&F4.| 000017b0 20 20 20 38 30 20 70 68 72 6f 6d 3d 26 46 35 0d | 80 phrom=&F5.| 000017c0 20 20 20 39 30 20 72 6f 6d 70 6f 69 6e 74 3d 26 | 90 rompoint=&| 000017d0 46 36 0d 20 20 31 30 30 20 62 72 65 61 6b 76 3d |F6. 100 breakv=| 000017e0 26 32 30 32 0d 20 20 31 31 30 20 67 73 72 65 61 |&202. 110 gsrea| 000017f0 64 3d 26 46 46 43 35 0d 20 20 31 32 30 20 6f 73 |d=&FFC5. 120 os| 00001800 62 79 74 65 3d 26 46 46 46 34 0d 20 20 31 33 30 |byte=&FFF4. 130| 00001810 20 46 4f 52 20 70 61 73 73 20 3d 20 30 20 54 4f | FOR pass = 0 TO| 00001820 20 32 20 53 54 45 50 20 32 0d 20 20 31 34 30 20 | 2 STEP 2. 140 | 00001830 50 25 3d 48 49 4d 45 4d 0d 20 20 31 35 30 20 5b |P%=HIMEM. 150 [| 00001840 20 20 20 20 20 20 20 4f 50 54 20 70 61 73 73 0d | OPT pass.| 00001850 20 20 31 36 30 20 20 20 20 20 20 20 20 20 4a 4d | 160 JM| 00001860 50 20 6c 61 6e 67 75 61 67 65 2b 64 69 66 66 0d |P language+diff.| 00001870 20 20 31 37 30 20 20 20 20 20 20 20 20 20 4a 4d | 170 JM| 00001880 50 20 73 65 72 76 69 63 65 2b 64 69 66 66 0d 20 |P service+diff. | 00001890 20 31 38 30 20 20 20 20 20 20 20 20 20 4f 50 54 | 180 OPT| 000018a0 20 46 4e 65 71 75 62 28 26 43 32 29 0d 20 20 31 | FNequb(&C2). 1| 000018b0 39 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 |90 OPT F| 000018c0 4e 65 71 75 62 28 28 63 6f 70 79 72 69 67 68 74 |Nequb((copyright| 000018d0 2b 64 69 66 66 29 20 4d 4f 44 20 32 35 36 29 0d |+diff) MOD 256).| 000018e0 20 20 32 30 30 20 20 20 20 20 20 20 20 20 42 52 | 200 BR| 000018f0 4b 0d 20 20 32 31 30 20 2e 74 69 74 6c 65 0d 20 |K. 210 .title. | 00001900 20 32 32 30 20 20 20 20 20 20 20 20 20 4f 50 54 | 220 OPT| 00001910 20 46 4e 65 71 75 73 28 22 52 46 53 22 29 0d 20 | FNequs("RFS"). | 00001920 20 32 33 30 20 2e 63 6f 70 79 72 69 67 68 74 0d | 230 .copyright.| 00001930 20 20 32 34 30 20 20 20 20 20 20 20 20 20 42 52 | 240 BR| 00001940 4b 0d 20 20 32 35 30 20 20 20 20 20 20 20 20 20 |K. 250 | 00001950 4f 50 54 20 46 4e 65 71 75 73 28 22 28 43 29 20 |OPT FNequs("(C) | 00001960 47 6f 72 64 6f 6e 20 48 6f 72 73 69 6e 67 74 6f |Gordon Horsingto| 00001970 6e 20 31 39 38 37 22 29 0d 20 20 32 36 30 20 20 |n 1987"). 260 | 00001980 20 20 20 20 20 20 20 42 52 4b 0d 20 20 32 37 30 | BRK. 270| 00001990 20 2e 73 65 72 76 69 63 65 0d 20 20 32 38 30 20 | .service. 280 | 000019a0 20 20 20 20 20 20 20 20 50 48 41 0d 20 20 32 39 | PHA. 29| 000019b0 30 20 20 20 20 20 20 20 20 20 43 4d 50 20 23 34 |0 CMP #4| 000019c0 0d 20 20 33 30 30 20 20 20 20 20 20 20 20 20 42 |. 300 B| 000019d0 4e 45 20 74 72 79 74 68 69 72 74 65 65 6e 0d 20 |NE trythirteen. | 000019e0 20 33 31 30 20 20 20 20 20 20 20 20 20 54 58 41 | 310 TXA| 000019f0 0d 20 20 33 32 30 20 20 20 20 20 20 20 20 20 50 |. 320 P| 00001a00 48 41 0d 20 20 33 33 30 20 20 20 20 20 20 20 20 |HA. 330 | 00001a10 20 54 59 41 0d 20 20 33 34 30 20 20 20 20 20 20 | TYA. 340 | 00001a20 20 20 20 50 48 41 0d 20 20 33 35 30 20 20 20 20 | PHA. 350 | 00001a30 20 20 20 20 20 4c 44 58 20 23 26 46 46 0d 20 20 | LDX #&FF. | 00001a40 33 36 30 20 2e 63 6f 6d 6c 6f 6f 70 0d 20 20 33 |360 .comloop. 3| 00001a50 37 30 20 20 20 20 20 20 20 20 20 49 4e 58 0d 20 |70 INX. | 00001a60 20 33 38 30 20 20 20 20 20 20 20 20 20 4c 44 41 | 380 LDA| 00001a70 20 74 69 74 6c 65 2b 64 69 66 66 2c 58 0d 20 20 | title+diff,X. | 00001a80 33 39 30 20 20 20 20 20 20 20 20 20 42 45 51 20 |390 BEQ | 00001a90 66 6f 75 6e 64 0d 20 20 34 30 30 20 20 20 20 20 |found. 400 | 00001aa0 20 20 20 20 4c 44 41 20 28 63 6f 6d 76 65 63 29 | LDA (comvec)| 00001ab0 2c 59 0d 20 20 34 31 30 20 20 20 20 20 20 20 20 |,Y. 410 | 00001ac0 20 49 4e 59 0d 20 20 34 32 30 20 20 20 20 20 20 | INY. 420 | 00001ad0 20 20 20 43 4d 50 20 23 41 53 43 28 22 2e 22 29 | CMP #ASC(".")| 00001ae0 0d 20 20 34 33 30 20 20 20 20 20 20 20 20 20 42 |. 430 B| 00001af0 45 51 20 66 6f 75 6e 64 0d 20 20 34 34 30 20 20 |EQ found. 440 | 00001b00 20 20 20 20 20 20 20 41 4e 44 20 23 26 44 46 0d | AND #&DF.| 00001b10 20 20 34 35 30 20 20 20 20 20 20 20 20 20 43 4d | 450 CM| 00001b20 50 20 74 69 74 6c 65 2b 64 69 66 66 2c 58 0d 20 |P title+diff,X. | 00001b30 20 34 36 30 20 20 20 20 20 20 20 20 20 42 45 51 | 460 BEQ| 00001b40 20 63 6f 6d 6c 6f 6f 70 0d 20 20 34 37 30 20 20 | comloop. 470 | 00001b50 20 20 20 20 20 20 20 50 4c 41 0d 20 20 34 38 30 | PLA. 480| 00001b60 20 20 20 20 20 20 20 20 20 54 41 59 0d 20 20 34 | TAY. 4| 00001b70 39 30 20 20 20 20 20 20 20 20 20 50 4c 41 0d 20 |90 PLA. | 00001b80 20 35 30 30 20 20 20 20 20 20 20 20 20 54 41 58 | 500 TAX| 00001b90 0d 20 20 35 31 30 20 20 20 20 20 20 20 20 20 50 |. 510 P| 00001ba0 4c 41 0d 20 20 35 32 30 20 20 20 20 20 20 20 20 |LA. 520 | 00001bb0 20 52 54 53 0d 20 20 35 33 30 20 2e 66 6f 75 6e | RTS. 530 .foun| 00001bc0 64 0d 20 20 35 34 30 20 20 20 20 20 20 20 20 20 |d. 540 | 00001bd0 4c 44 41 20 23 26 38 45 0d 20 20 35 35 30 20 20 |LDA #&8E. 550 | 00001be0 20 20 20 20 20 20 20 4c 44 58 20 72 6f 6d 6e 75 | LDX romnu| 00001bf0 6d 62 65 72 0d 20 20 35 36 30 20 20 20 20 20 20 |mber. 560 | 00001c00 20 20 20 4a 4d 50 20 6f 73 62 79 74 65 20 20 20 | JMP osbyte | 00001c10 20 5c 20 45 6e 74 65 72 20 74 68 69 73 20 52 4f | \ Enter this RO| 00001c20 4d 0d 20 20 35 37 30 20 2e 74 72 79 74 68 69 72 |M. 570 .trythir| 00001c30 74 65 65 6e 0d 20 20 35 38 30 20 20 20 20 20 20 |teen. 580 | 00001c40 20 20 20 43 4d 50 20 23 31 33 0d 20 20 35 39 30 | CMP #13. 590| 00001c50 20 20 20 20 20 20 20 20 20 42 4e 45 20 66 6f 75 | BNE fou| 00001c60 72 74 65 65 6e 0d 20 20 36 30 30 20 20 20 20 20 |rteen. 600 | 00001c70 20 20 20 20 54 59 41 0d 20 20 36 31 30 20 20 20 | TYA. 610 | 00001c80 20 20 20 20 20 20 45 4f 52 20 23 26 46 0d 20 20 | EOR #&F. | 00001c90 36 32 30 20 20 20 20 20 20 20 20 20 43 4d 50 20 |620 CMP | 00001ca0 72 6f 6d 6e 75 6d 62 65 72 0d 20 20 36 33 30 20 |romnumber. 630 | 00001cb0 20 20 20 20 20 20 20 20 42 43 43 20 6f 75 74 0d | BCC out.| 00001cc0 20 20 36 34 30 20 20 20 20 20 20 20 20 20 4c 44 | 640 LD| 00001cd0 41 20 23 28 6c 61 73 74 62 79 74 65 2b 64 69 66 |A #(lastbyte+dif| 00001ce0 66 29 20 4d 4f 44 20 32 35 36 0d 20 20 36 35 30 |f) MOD 256. 650| 00001cf0 20 20 20 20 20 20 20 20 20 53 54 41 20 72 6f 6d | STA rom| 00001d00 70 6f 69 6e 74 0d 20 20 36 36 30 20 20 20 20 20 |point. 660 | 00001d10 20 20 20 20 4c 44 41 20 23 28 6c 61 73 74 62 79 | LDA #(lastby| 00001d20 74 65 2b 64 69 66 66 29 20 44 49 56 20 32 35 36 |te+diff) DIV 256| 00001d30 0d 20 20 36 37 30 20 20 20 20 20 20 20 20 20 53 |. 670 S| 00001d40 54 41 20 72 6f 6d 70 6f 69 6e 74 2b 31 0d 20 20 |TA rompoint+1. | 00001d50 36 38 30 20 20 20 20 20 20 20 20 20 4c 44 41 20 |680 LDA | 00001d60 72 6f 6d 6e 75 6d 62 65 72 0d 20 20 36 39 30 20 |romnumber. 690 | 00001d70 20 20 20 20 20 20 20 20 45 4f 52 20 23 26 46 0d | EOR #&F.| 00001d80 20 20 37 30 30 20 20 20 20 20 20 20 20 20 53 54 | 700 ST| 00001d90 41 20 70 68 72 6f 6d 0d 20 20 37 31 30 20 2e 65 |A phrom. 710 .e| 00001da0 78 69 74 0d 20 20 37 32 30 20 20 20 20 20 20 20 |xit. 720 | 00001db0 20 20 50 4c 41 0d 20 20 37 33 30 20 20 20 20 20 | PLA. 730 | 00001dc0 20 20 20 20 4c 44 41 20 23 30 0d 20 20 37 34 30 | LDA #0. 740| 00001dd0 20 20 20 20 20 20 20 20 20 52 54 53 0d 20 20 37 | RTS. 7| 00001de0 35 30 20 2e 66 6f 75 72 74 65 65 6e 0d 20 20 37 |50 .fourteen. 7| 00001df0 36 30 20 20 20 20 20 20 20 20 20 43 4d 50 20 23 |60 CMP #| 00001e00 31 34 0d 20 20 37 37 30 20 20 20 20 20 20 20 20 |14. 770 | 00001e10 20 42 4e 45 20 6f 75 74 0d 20 20 37 38 30 20 20 | BNE out. 780 | 00001e20 20 20 20 20 20 20 20 4c 44 41 20 70 68 72 6f 6d | LDA phrom| 00001e30 0d 20 20 37 39 30 20 20 20 20 20 20 20 20 20 45 |. 790 E| 00001e40 4f 52 20 23 26 46 0d 20 20 38 30 30 20 20 20 20 |OR #&F. 800 | 00001e50 20 20 20 20 20 43 4d 50 20 72 6f 6d 6e 75 6d 62 | CMP romnumb| 00001e60 65 72 0d 20 20 38 31 30 20 20 20 20 20 20 20 20 |er. 810 | 00001e70 20 42 4e 45 20 6f 75 74 0d 20 20 38 32 30 20 20 | BNE out. 820 | 00001e80 20 20 20 20 20 20 20 4c 44 59 20 23 30 0d 20 20 | LDY #0. | 00001e90 38 33 30 20 20 20 20 20 20 20 20 20 4c 44 41 20 |830 LDA | 00001ea0 28 72 6f 6d 70 6f 69 6e 74 29 2c 59 0d 20 20 38 |(rompoint),Y. 8| 00001eb0 34 30 20 20 20 20 20 20 20 20 20 54 41 59 0d 20 |40 TAY. | 00001ec0 20 38 35 30 20 20 20 20 20 20 20 20 20 49 4e 43 | 850 INC| 00001ed0 20 72 6f 6d 70 6f 69 6e 74 0d 20 20 38 36 30 20 | rompoint. 860 | 00001ee0 20 20 20 20 20 20 20 20 42 4e 45 20 65 78 69 74 | BNE exit| 00001ef0 0d 20 20 38 37 30 20 20 20 20 20 20 20 20 20 49 |. 870 I| 00001f00 4e 43 20 72 6f 6d 70 6f 69 6e 74 2b 31 0d 20 20 |NC rompoint+1. | 00001f10 38 38 30 20 20 20 20 20 20 20 20 20 4a 4d 50 20 |880 JMP | 00001f20 65 78 69 74 2b 64 69 66 66 0d 20 20 38 39 30 20 |exit+diff. 890 | 00001f30 2e 6f 75 74 0d 20 20 39 30 30 20 20 20 20 20 20 |.out. 900 | 00001f40 20 20 20 50 4c 41 0d 20 20 39 31 30 20 20 20 20 | PLA. 910 | 00001f50 20 20 20 20 20 52 54 53 0d 20 20 39 32 30 20 2e | RTS. 920 .| 00001f60 6c 61 6e 67 75 61 67 65 0d 20 20 39 33 30 20 20 |language. 930 | 00001f70 20 20 20 20 20 20 20 43 4c 49 20 20 20 20 20 20 | CLI | 00001f80 20 20 20 20 20 5c 20 45 6e 61 62 6c 65 20 69 6e | \ Enable in| 00001f90 74 65 72 75 70 74 20 72 65 71 75 65 73 74 73 0d |terupt requests.| 00001fa0 20 20 39 34 30 20 20 20 20 20 20 20 20 20 4c 44 | 940 LD| 00001fb0 58 20 23 26 46 46 0d 20 20 39 35 30 20 20 20 20 |X #&FF. 950 | 00001fc0 20 20 20 20 20 54 58 53 20 20 20 20 20 20 20 20 | TXS | 00001fd0 20 20 20 5c 20 52 65 73 65 74 20 73 74 61 63 6b | \ Reset stack| 00001fe0 0d 20 20 39 36 30 20 20 20 20 20 20 20 20 20 4c |. 960 L| 00001ff0 44 41 20 23 28 62 61 73 69 63 2b 64 69 66 66 29 |DA #(basic+diff)| 00002000 20 4d 4f 44 20 32 35 36 0d 20 20 39 37 30 20 20 | MOD 256. 970 | 00002010 20 20 20 20 20 20 20 53 54 41 20 62 72 65 61 6b | STA break| 00002020 76 0d 20 20 39 38 30 20 20 20 20 20 20 20 20 20 |v. 980 | 00002030 4c 44 41 20 23 28 62 61 73 69 63 2b 64 69 66 66 |LDA #(basic+diff| 00002040 29 20 44 49 56 20 32 35 36 0d 20 20 39 39 30 20 |) DIV 256. 990 | 00002050 20 20 20 20 20 20 20 20 53 54 41 20 62 72 65 61 | STA brea| 00002060 6b 76 2b 31 0d 20 31 30 30 30 20 20 20 20 20 20 |kv+1. 1000 | 00002070 20 20 20 4c 44 41 20 23 26 38 44 0d 20 31 30 31 | LDA #&8D. 101| 00002080 30 20 20 20 20 20 20 20 20 20 4a 53 52 20 6f 73 |0 JSR os| 00002090 62 79 74 65 20 20 20 20 5c 20 2a 52 4f 4d 0d 20 |byte \ *ROM. | 000020a0 31 30 32 30 20 20 20 20 20 20 20 20 20 4c 44 41 |1020 LDA| 000020b0 20 23 26 38 42 0d 20 31 30 33 30 20 20 20 20 20 | #&8B. 1030 | 000020c0 20 20 20 20 4c 44 58 20 23 31 0d 20 31 30 34 30 | LDX #1. 1040| 000020d0 20 20 20 20 20 20 20 20 20 4c 44 59 20 23 30 0d | LDY #0.| 000020e0 20 31 30 35 30 20 20 20 20 20 20 20 20 20 4a 53 | 1050 JS| 000020f0 52 20 6f 73 62 79 74 65 20 20 20 20 5c 20 2a 4f |R osbyte \ *O| 00002100 50 54 31 2c 30 0d 20 31 30 36 30 20 20 20 20 20 |PT1,0. 1060 | 00002110 20 20 20 20 4c 44 41 20 23 26 30 46 0d 20 31 30 | LDA #&0F. 10| 00002120 37 30 20 20 20 20 20 20 20 20 20 4c 44 58 20 23 |70 LDX #| 00002130 30 0d 20 31 30 38 30 20 20 20 20 20 20 20 20 20 |0. 1080 | 00002140 4a 53 52 20 6f 73 62 79 74 65 20 20 20 20 5c 20 |JSR osbyte \ | 00002150 46 6c 75 73 68 20 61 6c 6c 20 62 75 66 66 65 72 |Flush all buffer| 00002160 73 0d 20 31 30 39 30 20 20 20 20 20 20 20 20 20 |s. 1090 | 00002170 4c 44 41 20 23 26 46 46 0d 20 31 31 30 30 20 20 |LDA #&FF. 1100 | 00002180 20 20 20 20 20 20 20 50 48 41 0d 20 31 31 31 30 | PHA. 1110| 00002190 20 2e 6b 65 79 62 6f 61 72 64 0d 20 31 31 32 30 | .keyboard. 1120| 000021a0 20 20 20 20 20 20 20 20 20 50 4c 41 0d 20 31 31 | PLA. 11| 000021b0 33 30 20 20 20 20 20 20 20 20 20 54 41 58 0d 20 |30 TAX. | 000021c0 31 31 34 30 20 20 20 20 20 20 20 20 20 49 4e 58 |1140 INX| 000021d0 0d 20 31 31 35 30 20 20 20 20 20 20 20 20 20 54 |. 1150 T| 000021e0 58 41 0d 20 31 31 36 30 20 20 20 20 20 20 20 20 |XA. 1160 | 000021f0 20 50 48 41 0d 20 31 31 37 30 20 20 20 20 20 20 | PHA. 1170 | 00002200 20 20 20 4c 44 59 20 72 66 73 63 6f 6d 6d 2b 64 | LDY rfscomm+d| 00002210 69 66 66 2c 58 0d 20 31 31 38 30 20 20 20 20 20 |iff,X. 1180 | 00002220 20 20 20 20 42 45 51 20 62 61 73 69 63 0d 20 31 | BEQ basic. 1| 00002230 31 39 30 20 20 20 20 20 20 20 20 20 4c 44 41 20 |190 LDA | 00002240 23 26 38 41 0d 20 31 32 30 30 20 20 20 20 20 20 |#&8A. 1200 | 00002250 20 20 20 4c 44 58 20 23 30 0d 20 31 32 31 30 20 | LDX #0. 1210 | 00002260 20 20 20 20 20 20 20 20 4a 53 52 20 6f 73 62 79 | JSR osby| 00002270 74 65 0d 20 31 32 32 30 20 20 20 20 20 20 20 20 |te. 1220 | 00002280 20 4a 4d 50 20 6b 65 79 62 6f 61 72 64 2b 64 69 | JMP keyboard+di| 00002290 66 66 0d 20 31 32 33 30 20 2e 62 61 73 69 63 0d |ff. 1230 .basic.| 000022a0 20 31 32 34 30 20 20 20 20 20 20 20 20 20 4c 44 | 1240 LD| 000022b0 41 20 23 26 42 42 0d 20 31 32 35 30 20 20 20 20 |A #&BB. 1250 | 000022c0 20 20 20 20 20 4c 44 58 20 23 30 0d 20 31 32 36 | LDX #0. 126| 000022d0 30 20 20 20 20 20 20 20 20 20 4c 44 59 20 23 26 |0 LDY #&| 000022e0 46 46 0d 20 31 32 37 30 20 20 20 20 20 20 20 20 |FF. 1270 | 000022f0 20 4a 53 52 20 6f 73 62 79 74 65 20 20 20 20 5c | JSR osbyte \| 00002300 20 46 69 6e 64 20 42 41 53 49 43 0d 20 31 32 38 | Find BASIC. 128| 00002310 30 20 20 20 20 20 20 20 20 20 4c 44 41 20 23 26 |0 LDA #&| 00002320 38 45 0d 20 31 32 39 30 20 20 20 20 20 20 20 20 |8E. 1290 | 00002330 20 4a 4d 50 20 6f 73 62 79 74 65 20 20 20 20 5c | JMP osbyte \| 00002340 20 45 6e 74 65 72 20 42 41 53 49 43 0d 20 31 33 | Enter BASIC. 13| 00002350 30 30 20 2e 72 66 73 63 6f 6d 6d 0d 20 31 33 31 |00 .rfscomm. 131| 00002360 30 20 20 20 20 20 20 20 20 20 4f 50 54 20 46 4e |0 OPT FN| 00002370 65 71 75 73 28 22 43 48 41 49 4e 22 22 44 45 4d |equs("CHAIN""DEM| 00002380 4f 22 22 22 29 0d 20 31 33 32 30 20 20 20 20 20 |O"""). 1320 | 00002390 20 20 20 20 4f 50 54 20 46 4e 65 71 75 62 28 26 | OPT FNequb(&| 000023a0 30 44 29 0d 20 31 33 33 30 20 20 20 20 20 20 20 |0D). 1330 | 000023b0 20 20 42 52 4b 0d 20 31 33 34 30 20 2e 6c 61 73 | BRK. 1340 .las| 000023c0 74 62 79 74 65 0d 20 31 33 35 30 20 5d 0d 20 31 |tbyte. 1350 ]. 1| 000023d0 33 36 30 20 4e 45 58 54 0d 20 31 33 37 30 20 4f |360 NEXT. 1370 O| 000023e0 25 3d 6c 61 73 74 62 79 74 65 0d 20 31 33 38 30 |%=lastbyte. 1380| 000023f0 20 43 48 41 49 4e 22 52 46 53 47 45 4e 22 0d 20 | CHAIN"RFSGEN". | 00002400 31 33 39 30 20 44 45 46 46 4e 65 71 75 62 28 62 |1390 DEFFNequb(b| 00002410 79 74 65 29 0d 20 31 34 30 30 20 3f 50 25 3d 62 |yte). 1400 ?P%=b| 00002420 79 74 65 0d 20 31 34 31 30 20 50 25 3d 50 25 2b |yte. 1410 P%=P%+| 00002430 31 0d 20 31 34 32 30 20 3d 70 61 73 73 0d 20 31 |1. 1420 =pass. 1| 00002440 34 33 30 20 44 45 46 46 4e 65 71 75 77 28 77 6f |430 DEFFNequw(wo| 00002450 72 64 29 0d 20 31 34 34 30 20 3f 50 25 3d 77 6f |rd). 1440 ?P%=wo| 00002460 72 64 20 4d 4f 44 20 32 35 36 0d 20 31 34 35 30 |rd MOD 256. 1450| 00002470 20 50 25 3f 31 3d 77 6f 72 64 20 44 49 56 20 32 | P%?1=word DIV 2| 00002480 35 36 0d 20 31 34 36 30 20 50 25 3d 50 25 2b 32 |56. 1460 P%=P%+2| 00002490 0d 20 31 34 37 30 20 3d 70 61 73 73 0d 20 31 34 |. 1470 =pass. 14| 000024a0 38 30 20 44 45 46 46 4e 65 71 75 64 28 64 6f 75 |80 DEFFNequd(dou| 000024b0 62 6c 65 29 0d 20 31 34 39 30 20 21 50 25 3d 64 |ble). 1490 !P%=d| 000024c0 6f 75 62 6c 65 0d 20 31 35 30 30 20 50 25 3d 50 |ouble. 1500 P%=P| 000024d0 25 2b 34 0d 20 31 35 31 30 20 3d 70 61 73 73 0d |%+4. 1510 =pass.| 000024e0 20 31 35 32 30 20 44 45 46 46 4e 65 71 75 73 28 | 1520 DEFFNequs(| 000024f0 73 74 72 69 6e 67 24 29 0d 20 31 35 33 30 20 24 |string$). 1530 $| 00002500 50 25 3d 73 74 72 69 6e 67 24 0d 20 31 35 34 30 |P%=string$. 1540| 00002510 20 50 25 3d 50 25 2b 4c 45 4e 28 73 74 72 69 6e | P%=P%+LEN(strin| 00002520 67 24 29 0d 20 31 35 35 30 20 3d 70 61 73 73 0d |g$). 1550 =pass.| 00002530