About Don Schullian Expertise I`ve worked in BASIC since the Commodore days and maintain a web site part of which is devoted to helping others with thier problems. I`m proficient in all versions of PowerBASIC but cross over to QuickBASIC and Qbasic frequently.
Question QUESTION: Hi there, I've been trying to write a program for C64 BASIC that uses a custom character set. According to the Programmer's Reference Guide I was advised to start at memory location 12288 using a POKE at 53272. The Programmer's Reference Guide states:
"The best place to put your character set for use with BASIC while
experimenting is beginning at 12288 ($3000 in HEX). This is done by
POKEing the low 4 bits of location 53272 with 12. Try the POKE now, like
this:
POKE 53272,(PEEK(53272)AND240)+12"
Suppose I need to put my character set at say 15000. What do I put into 53272 to make it read from there?
The reason why I want to move it from 12288 is because I'm running out of memory trying to redefine all 256 characters.
Can you help me?
ANSWER: I'm sorry, Mike, I have no idea how to do that. If I knew where my partner was from back in that era he may still remember but you'd be taxing some old man's brain on this one. ;)
Good Luck
---------- FOLLOW-UP ----------
QUESTION: Alright, well, supposedly 53272 holds the pointer byte for where to look in RAM...The +12 tells it to look at 12288 so would it be a matter of changing that number to correspond to the location I want?
Answer I'm taking a shot here. By poking 12 into the low nibble all you're doing is changing a portion of the address to the look-up table for the font. Beyond this I've no clue! I remember doing some of this when 1st learning programming on the C64 but we're talking about ancient history here and the ink on the walls of the cave have faded.
If you don't need the original font set then why not over wright the existing character data?
