NEC CP/M-86 - Page 187

Appendix C
Auxiliary Character
Generator RAM Format
Assembly language programs can access the auxiliary character generator RAM.
The auxiliary character generator files are created using the
CHR utility. (See
CPIM-86 System User's Guide for the APC.) This appendix includes a description of
the auxiliary character generator (CG) RAM address and format, and an explana-
tion
of how to load it.
AUXILIARY CHARACTER RAM ADDRESS AND FORMAT
D8000H
D9FEOH
...
I I
1<----- 32 bytes ----->f
I I
I I
I I
I I
I I
character 0
character 1
character 2
character 255
Corresponding
Auxiliary
Character Code
OOH
01 H
02H
FFH
The top address of the auxiliary CG RAM is D8000H. Each character is made up of
a 32-byte bit pattern. The high order byte of every word is all zeros. You must
transfer in words,
not bytes, to the auxiliary CG RAM. This is a hardware
restriction.
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