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That was necessary. Unlike the C64 the graphics chip in the 99/4A had its own memory not mapped into main CPU RAM. You had to write a lpad or store command with an address to the memory bus register and then read or write data to access the video RAM. There was an autoincrement so you could read or write multiple bytes with one command, but it was still slow. Oh, and guess where BASIC programs were stored? Video RAM. Guess how the interpreter was written? In an interpreted bytecode that was stored in video-bus ROM (called GROM). An unextended 99/4A had something like 256 BYTES of CPU RAM (it was fast expensive SRAM).

So yes, you had to use POKE commands, but an unexpanded C64 still gave you access to ALL its capabilities from BASIC (even the ability to write and call machine language programs from within BASIC). An unexpanded TI-99 gave you only as much as the BASIC authors provided CALL statements for. We were even cut off from sprites without the purchase of Extended BASIC.




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