402 B
402 B
Monochrome Video
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need 307 200 bits => 38 400/0x9600 Bytes
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8K character memory
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1x 64K RAM
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split in half
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each half into page (0x0000 - 0x4AFF)
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map character memory into top (0x6000 - 0x7FFF)
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offset of 0x6000 into memory bus -> (0x6000 - 0xAAFF), (0xC000 - 0xDFFF)
Design
- derive CS from bank register, leave LSB free -> wire to MSB of VRAM address