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Tricking c64 basic into clearing a hi-res screen quickly
Bitmap graphics with Commodore 64 BASIC 2.0 is not easy, but it is possible. The problem is the lack of commands specifically designed to handle the
If you have tried the programs from the Commodore 64 Programmer’s Reference Guide, you will have realized that clearing the bitmap screen is the most time-consuming operation. To speed things up, we could change the content of location 648 decimal so that it is possible to print characters on the same memory area the bitmap screen is placed to. Since the String Storage Area Pointer is on locations 51 and 52 decimal, if you issue the above statement in direct mode, it is easy to see where the value 65 will be stored in memory.
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