jdm:pc9801:ports
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Table of Contents
NEC PC-9801 - I/O Ports
02h
TODO
35h
TODO
37h
TODO
71h
TODO
73h
TODO
77h
TODO
7Ch (GRCG - Control)
* bit 7 - enable (1)/disable (0) GRCG * bit 6 - enable (1)/disable (0) read/modify/write mode * bit 4-5 - select plane exposed to CPU (0-3) * bit 3 - enable (1)/disable 0) plane 3 * bit 2 - enable (1)/disable 0) plane 2 * bit 1 - enable (1)/disable 0) plane 1 * bit 0 - enable (1)/disable 0) plane 0
7Eh (GRCG - Tile)
This port accepts sequential (in order of enabled planes) 8-bit tile data.
jdm/pc9801/ports.1645223784.txt.gz · Last modified: 2022/02/18 22:36 by asie