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25 lines
915 B
Markdown
25 lines
915 B
Markdown
# apple1-videocard-lib
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Library and demos for the Apple-1 TMS9918 video card by P-LAB.
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# Building for the "Juke Box" EPROM expansion
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The demo contained in the repo are meant to be launched from the Apple-1 "Juke Box"
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EPROM expansion at address $4000. The executables are built according to the
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following memory map:
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$0000-$00FF zero page: holds most of C program variables
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$0280-$0FFF low RAM space: C program "Data" segment
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$4000-$7581 EPROM (Juke Box): C program "Code" segment
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$7582-$7FFF EPROM (Juke Box): C program "Data" segment (startup values)
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The build script "mkeprom.js" creates a 16K binary file to be placed on the
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EPROM where the "Data" segment startup values are put at the end of the file itself.
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The user program need to manually copy such data from EPROM to low RAM once after
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the `main()` is launched. That can be easily done by simply calling the library
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function `apple1_eprom_init()`.
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