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02-12-88/FONTINF
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: | 02-12-88/FONTINF |
Read OK: | ✔ |
File size: | 18A9 bytes |
Load address: | 0000 |
Exec address: | 0000 |
Duplicates
There is 1 duplicate copy of this file in the archive:
- CEEFAX disks » telesoftware11.adl » 02-12-88/FONTINF
- CEEFAX disks » telesoftware17.adl » 30-07-89/FontInf
File contents
(c) Roxeysoft / M.J.Rawlings 14-2-88 FONT MASTER Font Master is a program that writes programs, you can use it to define fonts or sprites and then when you are satisfied with the result it will write the nescesary VDU definitions in a basic program and save it to disk. Very little explanation is needed to use the program, as instructions are displayed on screen where nescessary. The same is not true for the VDU definitions produced by the program. Different BBC type Acorn machines store the character definition codes in different areas of memory. The original BBC B had memory allocated for only 32 characters, whereas the Master, Compact and Archimedes have space for all 224 redefinable characters. The problem is that on the old BBC B this memory and the registers which control it are readily accessable, whereas on the latest machines it is not. For this reason the Font Master program does not actually redefine any characters but merely stores the codes needed to redefine, and displays the results. On running the program will display the current state of character definitions and on exit will leave the definitions as it found them, unless you exit by pressing break or control + break. If you have a Master or Compact or Archimedes little extra explanation is needed as you can change fonts by simply using the VDU23 commands produced by Font Master. The easiest way to incorporate them in your own program is to renumber them to line numbers higher than used by your own program, *SPOOL the result then *EXEC them into place:- RENUMBER 5000 *SPOOL MYFONT LIST *SPOOL LOAD"MYPROG" *EXEC MYFONT SAVE"MYPROG2" On the old BBC B if you define more than the characters 224 to 255 then you will have to get involved in allocating memory for storing the codes. The reccomended Acorn method is to use *FX20 but this means raising page to create room, if you wish to redefine all the characters from 32 to 255 then you would have to raise page from &1900 to &1F00 unless, of course, you have a second processor. There is an alternative method which involves accessing the font registers directly. These are stored at addresses &368 to &36E and are used to point to the page in memory where the character codes are stored, the default values for all these registers is &C. This does not mean that all 224 codes are stored at &C00 because there is also a register at &367 and bits 1 to 7 are used as flags to indicate whether a block of characters has its font in ROM (bit=0) or RAM (bit=1) :- Flag &367 Location Byte Character 32 to 63 bit 7 &368 Character 64 to 95 bit 6 &369 Character 96 to 127 bit 5 &36A Character 128 to 159 bit 4 &36B Character 160 to 191 bit 3 &36C Character 192 to 223 bit 2 &36D Character 224 to 255 bit 1 &36E The flag byte has a default value of 15 meaning that characters 32 to 127 are derived from ROM and the rest from RAM. As only one page of memory is allocated by Acorn the remaining 4 blocks of characters all obtain their definitons from the same font and are therefore identical. Redefining any character in a block automatically resets the appropriate bit to point to RAM, without allocating any more memory, thereby overwriting any other codes already stored in page &C00. If all this seems far too technical and hopelessly wasteful in memory then dont worry there is a simple solution. It is possible to use the memory allocated for the disk operating system, providing you do not intend to open more than one disk file at a time in your own program. Set the location flags for characters 32 to 223 to point to pages &1300 to &1800 :- FOR X=0 TO 5:?(&368+X)=&13+X:NEXT Then you are free to redefine all the characters from 32 to 255. You can have two complete new fonts of 96 characters plus 32 sprites simultaneously stored in memory. By juggling the registers you can switch instantly between your own two fonts and Acorn's original. Redefine characters 32 to 127 for font number one, use characters 128 to 223 for the second font leaving 224 to 255 for any additional sprites. Having done this you will find that your first font is the current version, switch back to Acorn's original font with the command:- ?&367=15 Convert back to your own first font with the command:- ?&367=127 Then you can change to font number two with the command:- FOR X=0 TO 2:?(&368)=&16+X:NEXT And back to the first font:- FOR X=0 TO 2:?(&368)=&13+X:NEXT Broadcast with the main FONT program is EXAMPLE, this is an example of a program written by the FONT program which is a long list of VDU23 statements all of which add up to two new fonts plus a few useful graphics characters. In addition I have added a few lines to illustrate the technique of swopping fonts on a BBC B. If you have a Master, Compact or Archimedes strip off lines 10 and 2270 to 2350. Note that you cannot swop fonts in the same way on the newer machines as the font data is not stored in main memory and the registers are not applicable. On a Master, Compact or Archimedes you will have to use VDU23 commands to alter all the codes from 32 to 127 every time you wish to change fonts. The old BEEB still has some advantages! You can examine the complete fonts by running the EXAMPLE program and then immediately running the FONT program. Font Master contains no non Acorn approved techniques and so is compatible with all BBC type machines. The only customising needed will be to change line 400 to allow 10 character filenames for use with the ADFS, this is clearly shown in the REM statements on lines 410 and 420.
00000000 0d 0d 0d 0d 0d 0d 0d 20 20 20 20 20 20 20 20 20 |....... | 00000010 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000020 20 20 20 20 20 20 20 20 20 28 63 29 20 52 6f 78 | (c) Rox| 00000030 65 79 73 6f 66 74 20 2f 20 4d 2e 4a 2e 52 61 77 |eysoft / M.J.Raw| 00000040 6c 69 6e 67 73 20 31 34 2d 32 2d 38 38 0d 0d 0d |lings 14-2-88...| 00000050 0d 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |. | 00000060 20 20 20 20 20 20 20 20 20 20 20 20 20 20 46 4f | FO| 00000070 4e 54 20 4d 41 53 54 45 52 0d 0d 0d 46 6f 6e 74 |NT MASTER...Font| 00000080 20 20 4d 61 73 74 65 72 20 20 69 73 20 20 61 20 | Master is a | 00000090 20 70 72 6f 67 72 61 6d 20 20 74 68 61 74 20 20 | program that | 000000a0 77 72 69 74 65 73 20 70 72 6f 67 72 61 6d 73 2c |writes programs,| 000000b0 20 79 6f 75 20 63 61 6e 20 75 73 65 20 69 74 20 | you can use it | 000000c0 74 6f 0d 64 65 66 69 6e 65 20 66 6f 6e 74 73 20 |to.define fonts | 000000d0 6f 72 20 73 70 72 69 74 65 73 20 61 6e 64 20 74 |or sprites and t| 000000e0 68 65 6e 20 20 77 68 65 6e 20 20 79 6f 75 20 20 |hen when you | 000000f0 61 72 65 20 20 73 61 74 69 73 66 69 65 64 20 20 |are satisfied | 00000100 77 69 74 68 20 20 74 68 65 0d 72 65 73 75 6c 74 |with the.result| 00000110 20 20 69 74 20 77 69 6c 6c 20 77 72 69 74 65 20 | it will write | 00000120 74 68 65 20 6e 65 73 63 65 73 61 72 79 20 56 44 |the nescesary VD| 00000130 55 20 64 65 66 69 6e 69 74 69 6f 6e 73 20 69 6e |U definitions in| 00000140 20 61 20 62 61 73 69 63 20 70 72 6f 67 72 61 6d | a basic program| 00000150 0d 61 6e 64 20 73 61 76 65 20 69 74 20 74 6f 20 |.and save it to | 00000160 64 69 73 6b 2e 0d 0d 56 65 72 79 20 6c 69 74 74 |disk...Very litt| 00000170 6c 65 20 65 78 70 6c 61 6e 61 74 69 6f 6e 20 69 |le explanation i| 00000180 73 20 6e 65 65 64 65 64 20 74 6f 20 75 73 65 20 |s needed to use | 00000190 74 68 65 20 70 72 6f 67 72 61 6d 2c 20 61 73 20 |the program, as | 000001a0 20 69 6e 73 74 72 75 63 74 69 6f 6e 73 0d 61 72 | instructions.ar| 000001b0 65 20 64 69 73 70 6c 61 79 65 64 20 6f 6e 20 73 |e displayed on s| 000001c0 63 72 65 65 6e 20 77 68 65 72 65 20 6e 65 73 63 |creen where nesc| 000001d0 65 73 73 61 72 79 2e 20 54 68 65 20 73 61 6d 65 |essary. The same| 000001e0 20 69 73 20 6e 6f 74 20 74 72 75 65 20 66 6f 72 | is not true for| 000001f0 20 74 68 65 0d 56 44 55 20 20 64 65 66 69 6e 69 | the.VDU defini| 00000200 74 69 6f 6e 73 20 20 70 72 6f 64 75 63 65 64 20 |tions produced | 00000210 20 62 79 20 20 74 68 65 20 20 70 72 6f 67 72 61 | by the progra| 00000220 6d 2e 20 44 69 66 66 65 72 65 6e 74 20 42 42 43 |m. Different BBC| 00000230 20 74 79 70 65 20 41 63 6f 72 6e 0d 6d 61 63 68 | type Acorn.mach| 00000240 69 6e 65 73 20 73 74 6f 72 65 20 74 68 65 20 63 |ines store the c| 00000250 68 61 72 61 63 74 65 72 20 64 65 66 69 6e 69 74 |haracter definit| 00000260 69 6f 6e 20 63 6f 64 65 73 20 69 6e 20 20 64 69 |ion codes in di| 00000270 66 66 65 72 65 6e 74 20 20 61 72 65 61 73 20 20 |fferent areas | 00000280 6f 66 0d 6d 65 6d 6f 72 79 2e 20 20 20 54 68 65 |of.memory. The| 00000290 20 20 6f 72 69 67 69 6e 61 6c 20 20 42 42 43 20 | original BBC | 000002a0 20 42 20 20 68 61 64 20 20 6d 65 6d 6f 72 79 20 | B had memory | 000002b0 20 61 6c 6c 6f 63 61 74 65 64 20 20 66 6f 72 20 | allocated for | 000002c0 20 6f 6e 6c 79 20 20 33 32 0d 63 68 61 72 61 63 | only 32.charac| 000002d0 74 65 72 73 2c 20 77 68 65 72 65 61 73 20 74 68 |ters, whereas th| 000002e0 65 20 4d 61 73 74 65 72 2c 20 43 6f 6d 70 61 63 |e Master, Compac| 000002f0 74 20 61 6e 64 20 41 72 63 68 69 6d 65 64 65 73 |t and Archimedes| 00000300 20 68 61 76 65 20 73 70 61 63 65 20 20 66 6f 72 | have space for| 00000310 0d 61 6c 6c 20 20 32 32 34 20 20 72 65 64 65 66 |.all 224 redef| 00000320 69 6e 61 62 6c 65 20 63 68 61 72 61 63 74 65 72 |inable character| 00000330 73 2e 20 54 68 65 20 70 72 6f 62 6c 65 6d 20 69 |s. The problem i| 00000340 73 20 74 68 61 74 20 6f 6e 20 74 68 65 20 6f 6c |s that on the ol| 00000350 64 20 42 42 43 20 42 0d 74 68 69 73 20 6d 65 6d |d BBC B.this mem| 00000360 6f 72 79 20 61 6e 64 20 74 68 65 20 72 65 67 69 |ory and the regi| 00000370 73 74 65 72 73 20 77 68 69 63 68 20 63 6f 6e 74 |sters which cont| 00000380 72 6f 6c 20 69 74 20 61 72 65 20 72 65 61 64 69 |rol it are readi| 00000390 6c 79 20 61 63 63 65 73 73 61 62 6c 65 2c 0d 77 |ly accessable,.w| 000003a0 68 65 72 65 61 73 20 6f 6e 20 74 68 65 20 6c 61 |hereas on the la| 000003b0 74 65 73 74 20 6d 61 63 68 69 6e 65 73 20 69 74 |test machines it| 000003c0 20 69 73 20 6e 6f 74 2e 20 46 6f 72 20 20 74 68 | is not. For th| 000003d0 69 73 20 20 72 65 61 73 6f 6e 20 20 74 68 65 20 |is reason the | 000003e0 20 46 6f 6e 74 0d 4d 61 73 74 65 72 20 20 70 72 | Font.Master pr| 000003f0 6f 67 72 61 6d 20 20 64 6f 65 73 20 20 6e 6f 74 |ogram does not| 00000400 20 61 63 74 75 61 6c 6c 79 20 72 65 64 65 66 69 | actually redefi| 00000410 6e 65 20 61 6e 79 20 63 68 61 72 61 63 74 65 72 |ne any character| 00000420 73 20 62 75 74 20 6d 65 72 65 6c 79 0d 73 74 6f |s but merely.sto| 00000430 72 65 73 20 74 68 65 20 63 6f 64 65 73 20 6e 65 |res the codes ne| 00000440 65 64 65 64 20 74 6f 20 72 65 64 65 66 69 6e 65 |eded to redefine| 00000450 2c 20 20 61 6e 64 20 20 64 69 73 70 6c 61 79 73 |, and displays| 00000460 20 20 74 68 65 20 20 72 65 73 75 6c 74 73 2e 20 | the results. | 00000470 20 4f 6e 0d 72 75 6e 6e 69 6e 67 20 20 74 68 65 | On.running the| 00000480 20 20 70 72 6f 67 72 61 6d 20 20 77 69 6c 6c 20 | program will | 00000490 20 64 69 73 70 6c 61 79 20 20 74 68 65 20 20 63 | display the c| 000004a0 75 72 72 65 6e 74 20 20 73 74 61 74 65 20 6f 66 |urrent state of| 000004b0 20 63 68 61 72 61 63 74 65 72 0d 64 65 66 69 6e | character.defin| 000004c0 69 74 69 6f 6e 73 20 61 6e 64 20 6f 6e 20 65 78 |itions and on ex| 000004d0 69 74 20 77 69 6c 6c 20 6c 65 61 76 65 20 74 68 |it will leave th| 000004e0 65 20 64 65 66 69 6e 69 74 69 6f 6e 73 20 61 73 |e definitions as| 000004f0 20 69 74 20 20 66 6f 75 6e 64 20 20 74 68 65 6d | it found them| 00000500 2c 0d 75 6e 6c 65 73 73 20 79 6f 75 20 65 78 69 |,.unless you exi| 00000510 74 20 62 79 20 70 72 65 73 73 69 6e 67 20 62 72 |t by pressing br| 00000520 65 61 6b 20 6f 72 20 63 6f 6e 74 72 6f 6c 20 2b |eak or control +| 00000530 20 62 72 65 61 6b 2e 0d 0d 49 66 20 79 6f 75 20 | break...If you | 00000540 68 61 76 65 20 61 20 4d 61 73 74 65 72 20 6f 72 |have a Master or| 00000550 20 43 6f 6d 70 61 63 74 20 6f 72 20 41 72 63 68 | Compact or Arch| 00000560 69 6d 65 64 65 73 20 6c 69 74 74 6c 65 20 65 78 |imedes little ex| 00000570 74 72 61 20 65 78 70 6c 61 6e 61 74 69 6f 6e 0d |tra explanation.| 00000580 69 73 20 20 6e 65 65 64 65 64 20 20 61 73 20 79 |is needed as y| 00000590 6f 75 20 63 61 6e 20 63 68 61 6e 67 65 20 66 6f |ou can change fo| 000005a0 6e 74 73 20 62 79 20 73 69 6d 70 6c 79 20 75 73 |nts by simply us| 000005b0 69 6e 67 20 74 68 65 20 56 44 55 32 33 20 63 6f |ing the VDU23 co| 000005c0 6d 6d 61 6e 64 73 0d 70 72 6f 64 75 63 65 64 20 |mmands.produced | 000005d0 62 79 20 46 6f 6e 74 20 4d 61 73 74 65 72 2e 20 |by Font Master. | 000005e0 54 68 65 20 65 61 73 69 65 73 74 20 77 61 79 20 |The easiest way | 000005f0 74 6f 20 69 6e 63 6f 72 70 6f 72 61 74 65 20 74 |to incorporate t| 00000600 68 65 6d 20 20 69 6e 20 20 79 6f 75 72 0d 6f 77 |hem in your.ow| 00000610 6e 20 20 70 72 6f 67 72 61 6d 20 20 69 73 20 20 |n program is | 00000620 74 6f 20 72 65 6e 75 6d 62 65 72 20 74 68 65 6d |to renumber them| 00000630 20 74 6f 20 6c 69 6e 65 20 6e 75 6d 62 65 72 73 | to line numbers| 00000640 20 68 69 67 68 65 72 20 74 68 61 6e 20 75 73 65 | higher than use| 00000650 64 20 62 79 0d 79 6f 75 72 20 6f 77 6e 20 70 72 |d by.your own pr| 00000660 6f 67 72 61 6d 2c 20 2a 53 50 4f 4f 4c 20 74 68 |ogram, *SPOOL th| 00000670 65 20 72 65 73 75 6c 74 20 74 68 65 6e 20 2a 45 |e result then *E| 00000680 58 45 43 20 74 68 65 6d 20 69 6e 74 6f 20 70 6c |XEC them into pl| 00000690 61 63 65 3a 2d 0d 0d 20 20 20 20 20 20 20 20 20 |ace:-.. | 000006a0 20 20 20 20 20 20 20 20 20 20 20 52 45 4e 55 4d | RENUM| 000006b0 42 45 52 20 35 30 30 30 0d 20 20 20 20 20 20 20 |BER 5000. | 000006c0 20 20 20 20 20 20 20 20 20 20 20 20 20 2a 53 50 | *SP| 000006d0 4f 4f 4c 20 4d 59 46 4f 4e 54 0d 20 20 20 20 20 |OOL MYFONT. | 000006e0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 4c | L| 000006f0 49 53 54 0d 20 20 20 20 20 20 20 20 20 20 20 20 |IST. | 00000700 20 20 20 20 20 20 20 20 2a 53 50 4f 4f 4c 0d 20 | *SPOOL. | 00000710 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000720 20 20 20 4c 4f 41 44 22 4d 59 50 52 4f 47 22 0d | LOAD"MYPROG".| 00000730 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000740 20 20 20 20 2a 45 58 45 43 20 4d 59 46 4f 4e 54 | *EXEC MYFONT| 00000750 0d 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |. | 00000760 20 20 20 20 20 53 41 56 45 22 4d 59 50 52 4f 47 | SAVE"MYPROG| 00000770 32 22 0d 0d 4f 6e 20 74 68 65 20 6f 6c 64 20 42 |2"..On the old B| 00000780 42 43 20 42 20 69 66 20 79 6f 75 20 64 65 66 69 |BC B if you defi| 00000790 6e 65 20 6d 6f 72 65 20 74 68 61 6e 20 74 68 65 |ne more than the| 000007a0 20 20 63 68 61 72 61 63 74 65 72 73 20 20 32 32 | characters 22| 000007b0 34 20 20 74 6f 20 20 32 35 35 0d 74 68 65 6e 20 |4 to 255.then | 000007c0 20 79 6f 75 20 20 77 69 6c 6c 20 20 68 61 76 65 | you will have| 000007d0 20 74 6f 20 67 65 74 20 69 6e 76 6f 6c 76 65 64 | to get involved| 000007e0 20 69 6e 20 61 6c 6c 6f 63 61 74 69 6e 67 20 6d | in allocating m| 000007f0 65 6d 6f 72 79 20 66 6f 72 20 73 74 6f 72 69 6e |emory for storin| 00000800 67 0d 74 68 65 20 63 6f 64 65 73 2e 20 54 68 65 |g.the codes. The| 00000810 20 72 65 63 63 6f 6d 65 6e 64 65 64 20 41 63 6f | reccomended Aco| 00000820 72 6e 20 6d 65 74 68 6f 64 20 69 73 20 74 6f 20 |rn method is to | 00000830 75 73 65 20 2a 46 58 32 30 20 62 75 74 20 74 68 |use *FX20 but th| 00000840 69 73 20 6d 65 61 6e 73 0d 72 61 69 73 69 6e 67 |is means.raising| 00000850 20 70 61 67 65 20 20 74 6f 20 20 63 72 65 61 74 | page to creat| 00000860 65 20 20 72 6f 6f 6d 2c 20 20 69 66 20 20 79 6f |e room, if yo| 00000870 75 20 20 77 69 73 68 20 20 74 6f 20 20 72 65 64 |u wish to red| 00000880 65 66 69 6e 65 20 20 61 6c 6c 20 20 74 68 65 0d |efine all the.| 00000890 63 68 61 72 61 63 74 65 72 73 20 66 72 6f 6d 20 |characters from | 000008a0 33 32 20 74 6f 20 32 35 35 20 74 68 65 6e 20 79 |32 to 255 then y| 000008b0 6f 75 20 77 6f 75 6c 64 20 68 61 76 65 20 74 6f |ou would have to| 000008c0 20 72 61 69 73 65 20 70 61 67 65 20 66 72 6f 6d | raise page from| 000008d0 20 26 31 39 30 30 0d 74 6f 20 26 31 46 30 30 20 | &1900.to &1F00 | 000008e0 75 6e 6c 65 73 73 2c 20 6f 66 20 63 6f 75 72 73 |unless, of cours| 000008f0 65 2c 20 79 6f 75 20 68 61 76 65 20 61 20 73 65 |e, you have a se| 00000900 63 6f 6e 64 20 70 72 6f 63 65 73 73 6f 72 2e 0d |cond processor..| 00000910 0d 0d 0d 0d 0d 0d 0d 0d 0d 0d 0d 0d 0d 0d 0d 0d |................| 00000920 0d 0d 0d 54 68 65 72 65 20 20 69 73 20 20 61 6e |...There is an| 00000930 20 20 61 6c 74 65 72 6e 61 74 69 76 65 20 20 6d | alternative m| 00000940 65 74 68 6f 64 20 20 77 68 69 63 68 20 20 69 6e |ethod which in| 00000950 76 6f 6c 76 65 73 20 61 63 63 65 73 73 69 6e 67 |volves accessing| 00000960 20 74 68 65 20 66 6f 6e 74 0d 72 65 67 69 73 74 | the font.regist| 00000970 65 72 73 20 64 69 72 65 63 74 6c 79 2e 20 54 68 |ers directly. Th| 00000980 65 73 65 20 61 72 65 20 73 74 6f 72 65 64 20 61 |ese are stored a| 00000990 74 20 61 64 64 72 65 73 73 65 73 20 26 33 36 38 |t addresses &368| 000009a0 20 74 6f 20 26 33 36 45 20 61 6e 64 20 61 72 65 | to &36E and are| 000009b0 0d 75 73 65 64 20 74 6f 20 70 6f 69 6e 74 20 74 |.used to point t| 000009c0 6f 20 74 68 65 20 70 61 67 65 20 69 6e 20 6d 65 |o the page in me| 000009d0 6d 6f 72 79 20 20 77 68 65 72 65 20 20 74 68 65 |mory where the| 000009e0 20 20 63 68 61 72 61 63 74 65 72 20 20 63 6f 64 | character cod| 000009f0 65 73 20 20 61 72 65 0d 73 74 6f 72 65 64 2c 20 |es are.stored, | 00000a00 20 74 68 65 20 20 64 65 66 61 75 6c 74 20 20 76 | the default v| 00000a10 61 6c 75 65 73 20 66 6f 72 20 61 6c 6c 20 74 68 |alues for all th| 00000a20 65 73 65 20 72 65 67 69 73 74 65 72 73 20 69 73 |ese registers is| 00000a30 20 26 43 2e 20 54 68 69 73 20 64 6f 65 73 0d 6e | &C. This does.n| 00000a40 6f 74 20 6d 65 61 6e 20 74 68 61 74 20 61 6c 6c |ot mean that all| 00000a50 20 32 32 34 20 63 6f 64 65 73 20 61 72 65 20 73 | 224 codes are s| 00000a60 74 6f 72 65 64 20 61 74 20 26 43 30 30 20 62 65 |tored at &C00 be| 00000a70 63 61 75 73 65 20 74 68 65 72 65 20 69 73 20 61 |cause there is a| 00000a80 6c 73 6f 20 61 0d 72 65 67 69 73 74 65 72 20 61 |lso a.register a| 00000a90 74 20 26 33 36 37 20 61 6e 64 20 62 69 74 73 20 |t &367 and bits | 00000aa0 31 20 74 6f 20 37 20 61 72 65 20 75 73 65 64 20 |1 to 7 are used | 00000ab0 61 73 20 66 6c 61 67 73 20 74 6f 20 69 6e 64 69 |as flags to indi| 00000ac0 63 61 74 65 20 77 68 65 74 68 65 72 0d 61 20 62 |cate whether.a b| 00000ad0 6c 6f 63 6b 20 6f 66 20 63 68 61 72 61 63 74 65 |lock of characte| 00000ae0 72 73 20 68 61 73 20 69 74 73 20 66 6f 6e 74 20 |rs has its font | 00000af0 69 6e 20 52 4f 4d 20 28 62 69 74 3d 30 29 20 6f |in ROM (bit=0) o| 00000b00 72 20 52 41 4d 20 28 62 69 74 3d 31 29 20 3a 2d |r RAM (bit=1) :-| 00000b10 0d 20 20 20 20 20 0d 20 20 20 20 20 20 20 20 20 |. . | 00000b20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000b30 20 46 6c 61 67 20 26 33 36 37 20 20 20 20 20 20 | Flag &367 | 00000b40 20 20 20 20 20 4c 6f 63 61 74 69 6f 6e 20 42 79 | Location By| 00000b50 74 65 0d 20 20 20 20 20 0d 20 20 20 20 20 43 68 |te. . Ch| 00000b60 61 72 61 63 74 65 72 20 33 32 20 74 6f 20 36 33 |aracter 32 to 63| 00000b70 20 20 20 20 20 62 69 74 20 37 20 20 20 20 20 20 | bit 7 | 00000b80 20 20 20 20 20 20 20 20 20 20 20 26 33 36 38 20 | &368 | 00000b90 0d 20 20 20 20 20 43 68 61 72 61 63 74 65 72 20 |. Character | 00000ba0 36 34 20 74 6f 20 39 35 20 20 20 20 20 62 69 74 |64 to 95 bit| 00000bb0 20 36 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | 6 | 00000bc0 20 20 20 26 33 36 39 0d 20 20 20 20 20 43 68 61 | &369. Cha| 00000bd0 72 61 63 74 65 72 20 39 36 20 74 6f 20 31 32 37 |racter 96 to 127| 00000be0 20 20 20 20 62 69 74 20 35 20 20 20 20 20 20 20 | bit 5 | 00000bf0 20 20 20 20 20 20 20 20 20 20 26 33 36 41 0d 20 | &36A. | 00000c00 20 20 20 20 43 68 61 72 61 63 74 65 72 20 31 32 | Character 12| 00000c10 38 20 74 6f 20 31 35 39 20 20 20 62 69 74 20 34 |8 to 159 bit 4| 00000c20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | 00000c30 20 26 33 36 42 0d 20 20 20 20 20 43 68 61 72 61 | &36B. Chara| 00000c40 63 74 65 72 20 31 36 30 20 74 6f 20 31 39 31 20 |cter 160 to 191 | 00000c50 20 20 62 69 74 20 33 20 20 20 20 20 20 20 20 20 | bit 3 | 00000c60 20 20 20 20 20 20 20 20 26 33 36 43 0d 20 20 20 | &36C. | 00000c70 20 20 43 68 61 72 61 63 74 65 72 20 31 39 32 20 | Character 192 | 00000c80 74 6f 20 32 32 33 20 20 20 62 69 74 20 32 20 20 |to 223 bit 2 | 00000c90 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 26 | &| 00000ca0 33 36 44 0d 20 20 20 20 20 43 68 61 72 61 63 74 |36D. Charact| 00000cb0 65 72 20 32 32 34 20 74 6f 20 32 35 35 20 20 20 |er 224 to 255 | 00000cc0 62 69 74 20 31 20 20 20 20 20 20 20 20 20 20 20 |bit 1 | 00000cd0 20 20 20 20 20 20 26 33 36 45 0d 0d 54 68 65 20 | &36E..The | 00000ce0 66 6c 61 67 20 62 79 74 65 20 68 61 73 20 61 20 |flag byte has a | 00000cf0 64 65 66 61 75 6c 74 20 76 61 6c 75 65 20 6f 66 |default value of| 00000d00 20 31 35 20 6d 65 61 6e 69 6e 67 20 74 68 61 74 | 15 meaning that| 00000d10 20 63 68 61 72 61 63 74 65 72 73 20 33 32 20 20 | characters 32 | 00000d20 74 6f 0d 31 32 37 20 20 61 72 65 20 20 64 65 72 |to.127 are der| 00000d30 69 76 65 64 20 20 66 72 6f 6d 20 52 4f 4d 20 61 |ived from ROM a| 00000d40 6e 64 20 74 68 65 20 72 65 73 74 20 66 72 6f 6d |nd the rest from| 00000d50 20 52 41 4d 2e 20 41 73 20 6f 6e 6c 79 20 6f 6e | RAM. As only on| 00000d60 65 20 70 61 67 65 20 6f 66 0d 6d 65 6d 6f 72 79 |e page of.memory| 00000d70 20 69 73 20 61 6c 6c 6f 63 61 74 65 64 20 62 79 | is allocated by| 00000d80 20 41 63 6f 72 6e 20 74 68 65 20 72 65 6d 61 69 | Acorn the remai| 00000d90 6e 69 6e 67 20 34 20 62 6c 6f 63 6b 73 20 6f 66 |ning 4 blocks of| 00000da0 20 63 68 61 72 61 63 74 65 72 73 20 20 61 6c 6c | characters all| 00000db0 0d 6f 62 74 61 69 6e 20 20 20 74 68 65 69 72 20 |.obtain their | 00000dc0 20 64 65 66 69 6e 69 74 6f 6e 73 20 20 66 72 6f | definitons fro| 00000dd0 6d 20 20 74 68 65 20 20 73 61 6d 65 20 20 66 6f |m the same fo| 00000de0 6e 74 20 20 61 6e 64 20 20 61 72 65 20 20 74 68 |nt and are th| 00000df0 65 72 65 66 6f 72 65 0d 69 64 65 6e 74 69 63 61 |erefore.identica| 00000e00 6c 2e 20 52 65 64 65 66 69 6e 69 6e 67 20 61 6e |l. 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