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Update vdu.asm

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Removed a hack in VDU driver that has existed for 8 years.  :-)
This commit is contained in:
Wayne Warthen
2020-03-15 09:09:59 -07:00
parent 09c673fbd0
commit 242a1ce108
1 changed files with 3 additions and 11 deletions
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14
Source/HBIOS/vdu.asm
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@@ -461,21 +461,13 @@ VDU_BLKCPY:
LD A,31 ; PREP VDU FOR DATA R/W
OUT (VDU_REG),A ; DO IT
LD HL,VDU_BUF ; HL POINTS TO WORK BUFFER
; LD C,VDU_RAMWR ; LOAD C WITH VDU WRITE REGISTER
LD C,VDU_RAMRD ; LOAD C WITH VDU READ REGISTER
VDU_BLKCPY1: ; VIDEO RAM -> BUFFER COPY LOOP
CALL VDU_WAITRDY ; WAIT FOR VDU
;;;;;;;;;;;;;;;;;
; INI IS NOT WORKING FOR ME, GARBAGE DATA READS, NO IDEA WHY
; INI ; READ BYTE, DEC B, INC HL
; IN A,(VDU_DATA) ; BOGUS READ TO INCREMENT VDU RAM ADDRESS!!!
; JR NZ,VDU_BLKCPY1 ; LOOP TILL DONE
;;;;;;;;;;;;;;;;;
IN A,(VDU_RAMRD) ; READ DATA BYTE
LD (HL),A ; SAVE IN BUFFER
INC HL ; BUMP SOURCE ADDRESS
INI ; READ BYTE, DEC B, INC HL
IN A,(VDU_DATA) ; BOGUS READ TO INCREMENT VDU RAM ADDRESS!!!
DJNZ VDU_BLKCPY1 ; LOOP TILL DONE
JR NZ,VDU_BLKCPY1 ; LOOP TILL DONE
; SETUP TO COPY FROM WORK BUFFER TO VDU DEST
POP BC ; RECOVER THE COPY LENGTH