Morechars

Loads a 768-byte replacement character set at 56576, prints the alphabet, then sets the CHARS system variable with POKE 23607,221 and lists the program again in the new font. POKE 23607,60 returns to the ROM character set.

This program is on side B of the Long Island Sinclair Timex (LIST) user group library tape #3.5. The font is saved as a separate CODE file named m.

Program Analysis

Program Structure

Line 10 loads the CODE; lines 20-50 print and list before and after the POKE; line 9998 saves the BASIC and the 768 bytes at 56576; line 9999 restores the ROM font.

Potential Issues

• CHARS must point 256 bytes below the first character, so a font loaded at 56576 needs POKE 23607,220, as the Bold Print program on this tape uses. With 221, every character is taken from 32 characters further into the font. This may be deliberate, to reach other glyphs in the block, but the listing does not say.

   10 LOAD ""CODE 
   20 PRINT "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
   25 LIST 
   30 POKE 23607,221
   50 LIST 
   60 STOP 
 9000 STOP 
 9998 SAVE "morechars" LINE 10: SAVE "m"CODE 56576,768
 9999 POKE 23607,60