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Rewrote GETHSR(), GETHSP(), GETVSR(), GETVSP()

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This commit is contained in:
Curtis F Kaylor 2019-09-23 23:05:27 -04:00
parent f81f76eefb
commit 303263e915
2 changed files with 77 additions and 37 deletions
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104
x16/include/vera.a02
View File

@ -43,53 +43,58 @@ GETBYT: JSR SETADR ;Set Vera Address
RTS
;getvsp() - Get Vertical Stop
;Destroys: TEMP0
;Affects: A
;Returns: Y,X = Vertical Stop
GETVSP: LDA #3 ;Set Lookup Index to Vertical Stop
.DC $2C ;Skip to GETHVS (BIT Absolute)
GETVSP: LDA #7 ;Set Reg Offset to Vertical Stop
JSR GETHVS ;Read Registers
LSR ;Shift Left One Bit
JMP GETVSS ;Then Four More Bits and Mask
;getvsr() - Get Vertical Start
;Destroys: TEMP0
;Affects: A
;Returns: Y,X = Vertical Start
GETVSR: LDA #2 ;Set Lookup Index to Vertical Start
.DC $2C ;Skip to GETHVS (BIT Absolute)
;gethsp() - Get Horizontal Stop
;Destroys: TEMP0
;Affects: A
;Returns: Y,X = Horizontal Start
GETHSP: LDA #1 ;Set Lookup Index to Horizontal Start
.DC $2C ;Skip to GETHVS (BIT Absolute)
GETVSR: LDA #6 ;Set Reg Offset to Vertical Start
JSR GETHVS ;Read Registers
GETVSS: LSR ;Shift Left Four Bit
LSR
LSR
LSR
AND #$01 ;Isolate Bit 0
TAY ;and Copy MSB to Y
RTS
;gethsp() - Get Horizontal Stop
;Affects: A
;Returns: Y,X = Horizontal Stop
GETHSP: LDA #5 ;Set Lookup Index to Horizontal Start
JSR GETHVS ;Read Registers
LSR ;Shift Left Two Bits
LSR
JMP GETHSS ;then Mask and Return
;gethsr() - Get Horizontal Start
;Destroys: TEMP0
;Affects: A
;Returns: Y,X = Horizontal Start
GETHSR: LDA #0 ;Set Lookup Index to Horizontal Start
GETHSR: LDA #4 ;Set Lookup Index to Horizontal Start
JSR GETHVS ;Read Registers
;.dc $ff ;debug
GETHSS: AND #$03 ;Isolate Bit 0
TAY ;and Copy MSB to Y
RTS
GETHVS: LDY GETHVM,X ;Get High Bits Mask
STY TEMP0 ;and Save It
LDY GETHVO,X ;Get High Bits Rotation Count
.DC $5A ;PHY ;And Save it on Stack
ORA #4 ;Convert Index to Register Offset
JSR GETDCR ;Read LSB from Register
;gethvs() - Get Start/Stop Low Byte and High Bits
;Args: X = Low Register
;Affects: Y
;Returns: A = High Bits
; X = Low Byte
GETHVS: JSR GETDCR ;Read LSB from Register
;.dc $ff ;debug
PHA ;and Save It
LDA #8 ;Load Register Offset for High Bits
STA $9F20 ;Set As Address LSB
LDA $9F23,X ;and Read High Byte from Data Port
AND TEMP0 ;and Isolate High Bits
.DC $FA ;PLX ;Restore LSB into X Register
.DC $7A ;PLY ;Restore Rotation Count into Y
BEQ GETHVY ;If Not Zero
GETHVR: LSR ;Shift Right One Bit
DEY ;Decrement Counter
BNE GETHVR ;and Loop if Not Zero
GETHVY: TYA ;Return MSB in Y Register
LDA $9F23,X ;and Read High Bits into A
.DC $FA ;PLX ;Restore LSB into X
RTS
GETHVM: .DC $03,$C0,$10,$20
GETHVO: .DC 0,2,4,5
;getiql() - Get Interrupt Line
;Affects: A
@ -130,6 +135,41 @@ GETINT: ORA #$10 ;Set Auto-Increment to 1
TAX ;Copy LSB to X
RTS
;sethsr() - Get Horizontal Start
;Affects: A
;Returns: Y,X = Horizontal Start
SETHSR: TYA ;Convert MSB to High Bits
AND #$03
ASL
ASL
STA TEMP0 ;and Save
TXA ;Copy LSB to Accumlator
LDX #5 ;Set Register Offset to Horizontal Start
JSR SETHVS ;Write LSB and Get High Bits
AND #$F3 ;Mask Start Stop High
JMP SETHST ;OR in High Bits and Write Back
;sethsr() - Get Horizontal Start
;Affects: A
;Returns: Y,X = Horizontal Start
SETHSR: TYA ;Convert MSB to High Bits
AND #$03
STA TEMP0 ;and Save
TXA ;Copy LSB to Accumlator
LDX #4 ;Set Register Offset to Horizontal Start
JSR SETHVS ;Write LSB and Get High Bits
AND #$FC ;Mask Start Stop High
SETHST: ORA TEMP0 ;OR in High Bits
STA $9F23,X ;and Write back to Register
RTS
SETHVS: JSR SETDCX ;Write LSB
LDA #8 ;Load Register Offset for High Bits
STA $9F20 ;Set As Address LSB
LDA $9F23,X ;and Read High Bits into A
RTS
;setvid() - Set Video Output Mode
;Args: A = Video Mode
; Y = Chroma Disabled

10
x16/testvera.c02
View File

@ -32,10 +32,10 @@ void passed() {
void prtayx(aa,yy,xx) {prhex(aa); prhex(yy); prhex(xx); putspc(); putspc();}
void prthvs() {
setdst(hstart);printf("HSTART=%w, ");
setdst(hstop);printf("HSTOP=%w, ");
setdst(vstart);printf("VSTART=%w, ");
setdst(vstop);printf("VSTOP=%w%n");
setdst(hstart);printf("HSTART=%w, "); //$0000
setdst(hstop);printf("HSTOP=%w, "); //$0280 (640)
setdst(vstart);printf("VSTART=%w, "); //$0000
setdst(vstop);printf("VSTOP=%w%n"); //$01E0 (480)
}
void prttmp() {
@ -110,7 +110,7 @@ main:
} while (i);
passed();
putln("TESTING GETHST(), GETHSP()");
putln("TESTING GETHSR(), GETHSP(), GETVSR(), GETVSP()");
hstart = gethsr();
hstop = gethsp();
vstart = getvsr();