appian.txt

比较详尽的VGA端口寄存器的文档

 AGX 98032

The Appian Renegade series uses a Cirrus Logic VGA chip (CL-GD5402/5420) for
 VGA modes and the AGX98032 for enhanced modes. The VGA can be disabled.

The older Appian Rendition series uses the TM 340 series (TIGA).

The AGX 98032 uses the I/O addresses 2B0h-2BFh and a 16K memory mapped area,
located at B000h, B400h, C000h, C400h, C800h, CC00h, D000h, D400h, D800h,
 DC00h, E000h, E400h, E800h or EC00h

2B0h D(R/W):  Host Ctl
bit  0
   3-4
    11  To reset the AGX, set this bit, wait ~200ms then clear it
    18
    20
 24-31

2B4h (R/W):
2B5h (R/W):  ISA Host Ctl
bit  5


 - 2B8-2BB: DAC regs 0-3 ?  2B4 has RS2/3
2BAh
2BBh

2BEh (R/W):
Selects the indexed register read or written at 2BFh

2BEh index 1Dh (R/W):

M+000h W(R/W):
bit 9-10
      13

M+032h (R/W):
bit    1  Clock chip Clock line
       2  Clock chip Data line

M+114h W(R/W):
M+116h W(R/W):
M+168h W(R/W):
M+16Ah W(R/W):
M+524h W(R/W):
M+712h (R/W):
bit 0-1
    2-3