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Added Functions for Layer Registers

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This commit is contained in:
Curtis F Kaylor 2019-09-25 15:56:26 -04:00
parent 303263e915
commit 3b74138826
3 changed files with 445 additions and 73 deletions
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325
x16/include/vera.a02
View File

@ -2,6 +2,14 @@
; Requires External Functions NYBCAT, NYBCUT
; and Variables TEMP0
;getadr() - Get Vera Address
;Args: A = Bank + Auto-Increment
; Y,X = Address
GETADR: LDX $9F20 ;Store Address LSB
LDY $9F21 ;Store Address MSB
LDA $9F22 ;Store Bank & Auto-Increment
RTS
;getvid() - Get Video Output Mode
;Returns: A = Video Mode
; Y = Chroma Disabled
@ -32,7 +40,7 @@ GETBDR: LDA #$03 ;Set Register Offset to Border Color
GETDCR: LDY #$00 ;Set MSB to Display Composer Page
TAX ;Set LSB to Register Offset
;and Execute GETREG
;getreg(addr);
;getreg(&addr);
;Args: Y,X = Address
;Returns: A = Mode
; X = Current Data Port
@ -42,6 +50,194 @@ GETBYT: JSR SETADR ;Set Vera Address
LDA $9F23,X ;Read LSB from Data Port
RTS
;getmem(count, &addr) - Read Array From Vera Memory
;Args: A = Number of Bytes to Read
; Y,X = Address of Array to Read Into
;Requires: setadr()
;Sets: DSTLO,DSTHI = Address of Array
; TEMP0 = Number of Bytes to Read
;Affects: A
;Returns: Y = Number of Bytes Read
; X = Current Data Port
GETMEM: JSR SETDST ;Save Destination Address
GETMEA: STA TEMP0 ;Save Number of Bytes
LDY #0 ;Initialize Counter
LDX $9F25 ;Get Current Data Port
GETMEL: LDA $9F23,X ;Read Byte from Data Port
STA (DSTLO),Y ;Store in Memory
INY ;Increment Counter
CPY TEMP0 ;If Limit Not Reached
BNE GETMEL ; Loop
;getmod() - Get Layer 0/1 Mode
;Args: A = Layer (0/1)
;Affects: Y
;Returns: A = Layer Mode
; X = Current Data Port
GETMOD: JSR GETLRC ;Read Register
LSR ;Shift Left Five Bits
LSR
LSR
LSR
RTS
;getenb() - Get Layer 0/1 Enabled
;Args: A = Layer (0/1)
;Affects: Y
;Returns: A = $FF - Layer Enabled
; $00 - Layer Disabled
; X = Current Data Port
GETENB: JSR GETLRC ;Read Register
AND #$01 ;Isolate Bit 1
BEQ GETENX ;If Set
LDA #$FF ; Return TRUE
GETENX: RTS ;Else Return FALSE
;getlrc() - Get Layer 0/1 Control Register
;Args: A = Layer (0/1)
;Affects: Y
;Returns: A = Control Register Contents
; X = Current Data Port
GETLRC: LDX #0 ;Set Offset to Control Register
;getlrr() - Get Layer 0/1 Register
;Args: A = Layer (0/1)
; X = Register Offset
;Affects: Y
;Returns: A = Contents of Register
; X = Current Data Port
GETLRR: JSR GETLRP ;Get Layer Page in Y
BNE GETREG ;and Read Register Contents
;getlrp() - Get Layer 0/1 Register Page
;Args: A = Layer (0/1)
;Returns: A,Y = Layer Register Page
GETLRP: AND #$01 ;Isolate Bit 1
ASL ;Move to Left Nybble
ASL
ASL
ASL
ORA #$20 ;And Add to 2
TAY ;Return Page in Y
RTS
;getchd(index, &array) - Read Character Data into Array
;Args: A = Character Index
; Y,X = Address of Array to Read into
;Destroys: TEMP0,TEMP1,TEMP2
;Returns: A = Number of Bytes Read
GETCHD: JSR SETDST ;Store Address in Destination Pointer
STA TEMP1 ;Set Offset LSB to Index
LDA #0 ;Set Offset MSB to Zero
ASL TEMP1 ;Multiple Offset by 2
ROL
STA TEMP2 ;and Store MSB
JSR GETLRI ;Get Tile Base
TXA ;Add Offset To Tile Base
CLC
ADC TEMP0
STA TEMP0
TYA
ADC TEMP1
STA TEMP1
LDA #0
ADC #0
JSR GETMBX ;Multiply by 4
ORA #$10 ;Set Auto-Increment to 1
JSR SETADR ;and Set Vera Address
LDA #8 ;Set Byte Count to 8
BNE GETMEA ;and Read Bytes into Array
;gettba() - Get Layer 0/1 Tile Base Address
;Args: A = Layer (0/1)
;Destroys: TEMP1,TEMP2
;Returns: A = Tile Base Bank
; Y,X = Tile Base Address
GETTBA: LDX #4 ;Set Register Offset
.DC $2C ;Read Register Pair and Rotate
;getmba() - Get Layer 0/1 Map Base Address
;Args: A = Layer (0/1)
;Destroys: TEMP1,TEMP2
;Returns: A = Map Base Bank
; Y,X = Map Base Address
GETMBA: LDX #2 ;Set Register Offset
JSR GETLRI ;Read Register Pair as Integer
LDA #0 ;Initialize Page to 0
JSR SAVRXY ;Save Integer in TEMP1,TEMP2
GETMBX: LDX #2 ;Do Twice
GETMBL: ASL TEMP1 ; Rotate LSB
ROL TEMP2 ; MSB and
ROL ; Bank Left
DEX
BNE GETMBL
JMP RESRXY ;Load LSB, MSB and Return
;getvsc() - Get Layer 0/1 Vertical Scroll
;Args: A = Layer (0/1)
;Returns: A,X = Vertical Scroll LSB
; Y = Vertical Scroll MSB
GETVSC: LDX #8 ;Set Register Offset
.DC $2C ;Skip to GETLRI (BIT Absolute)
;gethsc() - Get Layer 0/1 Horizontal Scroll
;Args: A = Layer (0/1)
;Returns: A,X = Horizontal Scroll LSB
; Y = Horizontal Scroll MSB
GETHSC: LDX #6 ;Set Register Offset
.DC $2C ;Skip to GETLRI (BIT Absolute)
;gettbs() - Get Layer 0/1 Tile Base
;Args: A = Layer (0/1)
;Returns: A,X = Tile Base LSB
; Y = Tile Base MSB
GETTBS: LDX #4 ;Set Register Offset
.DC $2C ;Skip to GETLRI (BIT Absolute)
;getmbs() - Get Layer 0/1 Map Base
;Args: A = Layer (0/1)
;Returns: A,X = Map Base LSB
; Y = Map Base MSB
GETMBS: LDX #2 ;Set Register Offset
;getlri() - Get Layer 0/1 Register Pair as Integer
;Args: A = Layer (0/1)
; X = Register Offset
;Returns: A,X = Integer LSB
; Y = Integer LSB
GETLRI: JSR GETLRP ;Get Layer Page in Y
BNE GETREI ;and Read Register Contents
;mapsiz() - Convert Map Size Specifier to Pixels
;Args: A = Map Size Specifier
;Affects: A
;Returns: Y,X Map Size in Pixels
MAPSIZ: TAX ;Copy Map Size Specifier to X
LDA MAPSIH,X ;Load Pixels MSB from Table
TAY ;and Return in Y
LDA MAPSIL,X ;Load Pixels LSB from Table
TAX ;and Return in X
MAPSIL: .DC $20,$40,$80,$00
MAPSIH: .DC $00,$00,$00,$01
;tilsiz() - Convert Tile Size Specifier to Pixels
;Args: A = Tile Size Specifier
;Affects: A
;Returns: A Tile Size in Pixels
TILSIZ: TAX ;Copy Map Size Specifier to X
LDA TILSIT,X ;Load Pixels MSB from Table
RTS
TILSIT: .DC $08,$10
;gettsz() - Get Layer 0/1 Tile Size
;getmsz() - Get Layer 0/1 Map Size
;Args: A = Layer (0/1)
;Affects: X
;Returns: A = Map Width Specifier
; Y = Map Height Specifier
;getvsp() - Get Vertical Stop
;Affects: A
;Returns: Y,X = Vertical Stop
@ -99,13 +295,14 @@ GETHVS: JSR GETDCR ;Read LSB from Register
;getiql() - Get Interrupt Line
;Affects: A
;Returns: Y,X = Interrupt Line#
GETIQL: LDA #9 ;Set Register Offset to HSCALE,VSCALE
GETIQL: LDA #9 ;Set Register Offset to Interrupt Line
.DC $2C ;Skip to SETDCX (BIT Absolute)
;getscl() - Get Horizontal and Vertical Scale
;Returns: A,X = Horizontal Scale
; Y = Vertical Scale
GETSCL: LDA #1 ;Set Register Offset to HSCALE,VSCALE
.DC $2C ;Skip to SETDCI (BIT Absolute)
;getdci() - Get Display Composer Register Pair
;Args: A = Register Offset
@ -135,31 +332,64 @@ 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
;setvsp() - Set Horizontal Stop
;Args: Y,X = Horizontal Stop
;Affects: A,X,Y
SETVSP: TYA ;Convert MSB to High Bit
AND #$01
ASL
ASL
STA TEMP0 ;and Save
ASL
ASL
ASL
STA TEMP1 ;and Save
TXA ;Copy LSB to Accumlator
LDX #5 ;Set Register Offset to Horizontal Start
JSR SETHVS ;Write LSB and Get High Bits
AND #$F3 ;Mask Start Stop High
LDX #7 ;Set Register Offset to Horizontal Start
LDY #$DF ;Set High Bits Mask
JMP SETHST ;OR in High Bits and Write Back
;sethsr() - Get Horizontal Start
;Affects: A
;Returns: Y,X = Horizontal Start
;setvsr() - Set Horizontal Start
;Args: Y,X = Horizontal Start
;Affects: A,X,Y
SETVSR: TYA ;Convert MSB to High Bit
AND #$01
ASL
ASL
ASL
ASL
STA TEMP1 ;and Save
TXA ;Copy LSB to Accumlator
LDX #6 ;Set Register Offset to Horizontal Start
LDY #$EF ;Set High Bits Mask
JMP SETHST ;OR in High Bits and Write Back
;sethsp() - Set Horizontal Stop
;Args: Y,X = Horizontal Stop
;Affects: A,X,Y
SETHSP: TYA ;Convert MSB to High Bits
AND #$03
ASL
ASL
STA TEMP1 ;and Save
TXA ;Copy LSB to Accumlator
LDX #5 ;Set Register Offset to Horizontal Start
LDY #$F3 ;Set High Bits Mask
JMP SETHST ;OR in High Bits and Write Back
;sethsr() - Set Horizontal St7art
;Args: Y,X = Horizontal Start
;Destroys TEMP0,TEMP1,TEMP2
;Affects: A,X,Y
SETHSR: TYA ;Convert MSB to High Bits
AND #$03
STA TEMP0 ;and Save
STA TEMP1 ;and Save
TXA ;Copy LSB to Accumlator
LDX #4 ;Set Register Offset to Horizontal Start
LDY #$FC ;Set High Bits Mask
SETHST: STY TEMP2 ;Save
JSR SETHVS ;Write LSB and Get High Bits
AND #$FC ;Mask Start Stop High
SETHST: ORA TEMP0 ;OR in High Bits
AND TEMP2 ;Mask Start Stop High
ORA TEMP1 ;OR in High Bits
STA $9F23,X ;and Write back to Register
RTS
@ -221,6 +451,48 @@ SETBYT: JSR SETADR ;Set Vera Address
STA $9F23,X ;Write Value to Data Port
RTS
;settbs() - Set Layer 0/1 Map Base
;Args: A = Layer (0/1)
; Y,X = Map Base
;Sets: TEMP1,TEMP2 = Map Base
;Affecta: A,Y,X
SETTBS: JSR SAVRXY ;Store Map Base in TEMP1,TEMP2
LDX #4 ;Set Register Offset
BNE SETLRI ;Write to Layer Register
;setmbs() - Set Layer 0/1 Map Base
;Args: A = Layer (0/1)
; Y,X = Map Base
;Sets: TEMP1,TEMP2 = Map Base
;Affecta: A,Y,X
SETMBS: JSR SAVRXY ;Store Map Base in TEMP1,TEMP2
LDX #2 ;Set Register Offset
BNE SETLRI ;Write to Layer Register
;setvsc() - Set Layer 0/1 Vertical Scroll
;Args: A = Layer (0/1)
; Y,X = Map Base
;Sets: TEMP1,TEMP2 = Vertical Scroll
;Affecta: A,Y,X
SETVSC: JSR SAVRXY ;Store Vertical Scroll in TEMP1,TEMP2
LDX #8 ;Set Register Offset
BNE SETLRI ;Write to Layer Register
;sethsc() - Set Layer 0/1 Horizontal Scroll
;Args: A = Layer (0/1)
; Y,X = Map Base
;Sets: TEMP1,TEMP2 = Horizontal Scroll
;Affecta: A,Y,X
SETHSC: JSR SAVRXY ;Store Horizontal Scroll in TEMP1,TEMP2
LDX #6 ;Set Register Offset
;setlri() - Write Integer to Get Layer 0/1 Register
;Args: A = Layer (0/1)
; X = Register Offset
;Uses: TEMP1,TEMP2 = Integer Value
;Affecta: A,Y,X
SETLRI: JSR GETLRP ;Get Layer Page in Y
BNE SETREI ;and Write Integer to Register
;setiql() - Set IRQ Line
;Args: Y,X = IRQ Line Number`
@ -267,6 +539,25 @@ SETINT: ORA #$10 ;Set Auto-Increment to 1
STA $9F23,X ;Write to Data Port
RTS
;setmem(count, &addr) - Write Array to Vera Memory
;Args: A = Number of Bytes to Write
; Y,X = Address of Array to Write From
;Requires: setadr()
;Sets: SRCLO,SRCHI = Address of Array
; TEMP0 = Number of Bytes to Write
;Affects: A
;Returns: Y = Number of Bytes Written
; X = Current Data Port
SETMEM: STA TEMP0 ;Save Number of Bytes
JSR SETSRC ;Save Destination Address
LDX $9F25 ;Get Current Data Port
LDY #0 ;Initialize Counter
SETMEL: LDA (SRCLO),Y ;Read Byte from Array
STA $9F23,X ;Write Byte to Data Port
INY ;Increment Counter
CPY TEMP0 ;If Limit Not Reached
BNE SETMEL ; Loop
RTS
;rgbclr(r,g,b) - Convert RGB Values to Palette Color
;Args: A = Red Value (0-15)

36
x16/include/vera.h02
View File

@ -2,30 +2,6 @@
* vera.h02 - Commander X16 Routines for Vera chip *
***************************************************/
/* Convert Palette Color Value *
* to R, G, and B Values *
* Args: int c - Color Value *
* Returns: Red Value (0-15) *
* Green Value (0-15) *
* Blue Value (0-15) */
char clrrgb();
/* Read Color Value from Palette *
* Args: char i - Palette Index *
* Returns: int c - Color Value */
char getclr();
/* Read Display Controller Register *
* Args: char r - Register Offset *
* Returns: char v - Register Value */
char getdcr();
/* Read Video Output Mode *
* Returns: m - Output Mode *
* c - Chroma Disabled *
* f - Current Field */
char getvid();
/* Convert R, G, and B Values *
* to Palette Color Value *
* Args: r - Red Value (0-15) *
@ -34,9 +10,11 @@ char getvid();
* Returns: int c - Color Value */
char rgbclr();
/* Write Color Value to Palette *
* Args: i - Index into Palette *
* int c - Color Value *
* Returns: int d = Entry Address */
char setclr();
/* Convert Palette Color Value *
* to R, G, and B Values *
* Args: int c - Color Value *
* Returns: Red Value (0-15) *
* Green Value (0-15) *
* Blue Value (0-15) */
char clrrgb();

157
x16/testvera.c02
View File

@ -9,24 +9,52 @@
#include <intlib.h02>
#include <stdio.h02>
#include <stdiox.h02>
#include <memory.h02>
#include <nybble.h02>
#include "include/vera.h02"
const char abcdef = {1,2,3,4,5,6};
char buffer[255]; //Buffer for getmem
char hscale,vscale; //Video Scaling
char hrzvrt[5]; //Horizontal and Vertical Register Contents
char index; //Color Palette Index
char mode,mono,field; //Video Output Mode, Monochrome Flag, Current Field
char red,green,blue; //Color Components
char enabld; //Layer Enabled
char i,j,k,l;
int c,d,s;
int color,colour;
int hstart,hstop; //Horizontal Start and Stop
int vstart,vstop; //Vertical Start and Stop
int irqlin; //IRQ Line#
/* Layer 0/1 */
char layer; //Layer Number
char layer0[9]; //Layer 0 Register Contents
char layer1[9]; //Layer 1 Register Contents
int mbase0,mbase1; //Map Base, Layer 0 and 1
int tbase0,tbase1; //Tile Base, Layer 0 and 1
int mbaddr,tbaddr; //Map and Tile Base Address
int hscrl0,hscrl1; //Horizontal Scroll, Layer 0 and 1
int vscrl0,vscrl1; //Vertical Scroll, Layer 0 and 1
char aa,xx,yy;
void failed() {
putln(" FAILED");
}
void passed() {
putln(" PASSED");
newlin();
//newlin();
}
void prtadr() {
aa, yy, xx = getadr();
puts("ADDRESS=");
prbyte(aa); prbyte(yy); prbyte(xx); newlin();
}
void prtayx(aa,yy,xx) {prhex(aa); prhex(yy); prhex(xx); putspc(); putspc();}
@ -72,7 +100,13 @@ void xerror() {
main:
newlin();
putln("TESTING GETVID() AND SETVID()");
puts("TESTING GETMEM() AND SETMEM()");
setadr($20,&0); setmem(@abcdef,&abcdef);
setadr($20,&0); getmem(@abcdef,&buffer);
setdst(&abcdef); if (memcmp(@abcdef,&buffer)) xerror();
passed();
puts("TESTING GETVID() AND SETVID()");
for (i=0;i<4;i++) {
for (j=1;j:+;j--) {
//inline $ff;
@ -84,7 +118,7 @@ main:
}
passed();
putln("TESTING GETBDR() AND SETBDR()");
puts("TESTING GETBDR() AND SETBDR()");
i = 0;
do {
setbdr(i);
@ -95,7 +129,7 @@ main:
} while(i);
passed();
putln("TESTING GETSCL() AND SETSCL()");
puts("TESTING GETSCL() AND SETSCL()");
i=1;
do {
j=1;
@ -110,15 +144,35 @@ main:
} while (i);
passed();
putln("TESTING GETHSR(), GETHSP(), GETVSR(), GETVSP()");
hstart = gethsr();
hstop = gethsp();
vstart = getvsr();
vstop = getvsp();
prthvs();
newlin();
//putln("SAVING START AND STOP REGISTERS");
setadr($1F, &$0004); getmem(5, &hrzvrt);
//for (i=0;i<5;i++) printf(hrzvrt[i], "%h "); newlin();
puts("TESTING GETHSR() AND SETHSR()");
sethsr(&$024C);
hstart = gethsr();
//setdst(hstart);printf("HSTART=%w%n");
if (>hstart<>$02 or <hstart<>$4C) xerror(); else passed();
putln("TESTING GETIRL() AND SETIRL()");
puts("TESTING GETHSP() AND SETHSP()");
sethsp(&$025D); hstop = gethsp();
//setdst(hstop);printf("HSTOP=%w%n");
if (>hstop<>$02 or <hstop<>$5D) xerror(); else passed();
puts("TESTING GETVSR() AND SETVSR()");
setvsr(&$016E); vstart = getvsr();
//setdst(vstart);printf("VSTART=%w%n");
if (>vstart<>$01 or <vstart<>$6E) xerror(); else passed();
puts("TESTING GETVSP() AND SETVSP()");
setvsp(&$017F); vstop = getvsp();
//setdst(vstop);printf("VSTOP=%w%n");
if (>vstop<>$01 or <vstop<>$7F) xerror(); else passed();
//putln("RESTORING START AND STOP REGISTERS");
setadr($1F, &$0004); setmem(5, &hrzvrt);
puts("TESTING GETIRL() AND SETIRL()");
for (i=0;i<2;i++) {
j=0;
do {
@ -131,13 +185,13 @@ main:
}
passed();
putln("TESTING RGBCLR() AND CLRRGB()");
puts("TESTING RGBCLR() AND CLRRGB()");
for (red=0;red<16;red++) {
for (green=0;green<16;green++) {
for (blue=0;blue<16;blue++) {
//prtayx(red,green,blue);
c = rgbclr(red,green,blue);
//putwrd(c); putspc();
color = rgbclr(red,green,blue);
//putwrd(color); putspc();
i,j,k = clrrgb();
//prtayx(i,j,k);
if (i<>red or j<>green or blue<>k) xerror();
@ -147,30 +201,79 @@ main:
}
passed();
putln("TESTING GETCLR()");
puts("TESTING GETCLR() AND SETCLR()");
for (i=16; i<32; i++) {
//puthex(i); putspc();
c = getclr(i);
//putwrd(c); putspc();
if (i&15<>>c or nybdup(i)<><c) xerror();
color = getclr(i);
//putwrd(color); putspc();
if (i&15<>>color or nybdup(i)<><color) xerror();
//if (i&7==7) newlin();
}
passed();
//passed();
putln("TESTING SETCLR()");
//puts("TESTING SETCLR()");
for (i=128; i<144; i++) {
//puthex(i); putspc();
red = i+8&15;
green = 144-i;
blue = i&15;
//prhex(red); prhex(green); prhex(blue); putspc(); putspc();
c = rgbclr(red,green,blue);
setclr(i,c);
d = getclr(i);
//putwrd(d); putspc();
if (<d<><c or >d<>>c) xerror();
color = rgbclr(red,green,blue);
setclr(i,color);
colour = getclr(i);
//putwrd(colour); putspc();
if (<colour<><color or >colour<>>color) xerror();
//if (i&7==7) newlin();
}
passed();
//putln("SAVING LAYER REGISTERS");
setadr($1F,&$2000); getmem(@layer0,&layer0);
setadr($1F,&$3000); getmem(@layer1,&layer1);
printf(layer, "TESTING GETMBS() AND SETMBS()");
setmbs(0,&$1234); mbase0 = getmbs(0);
setmbs(1,&$5678); mbase1 = getmbs(1);
//setdst(mbase0); printf("%nMBASE0=$%w, "); setdst(mbase1); printf("MBASE1=$%w%n");
if (>mbase0<>$12 or <mbase0<>$34) xerror();
if (>mbase1<>$56 or <mbase1<>$78) xerror();
passed();
printf(layer, "TESTING GETTBS() AND SETTBS()");
settbs(0,&$90AB); tbase0 = gettbs(0);
settbs(1,&$CDEF); tbase1 = gettbs(1);
//setdst(tbase0); printf("%nTBASE0=$%w, "); setdst(tbase1); printf("TBASE1=$%w%n");
if (>tbase0<>$90 or <tbase0<>$AB) xerror();
if (>tbase1<>$CD or <tbase1<>$EF) xerror();
passed();
printf(layer, "TESTING GETMBA() AND GETTBA()");
i,j,k = getmba(0); if (i<>$00 or j<>$48 or k<>$D0) xerror();
i,j,k = getmba(1); if (i<>$01 or j<>$59 or k<>$E0) xerror();
i,j,k = gettba(0); if (i<>$02 or j<>$42 or k<>$AC) xerror();
i,j,k = gettba(1); if (i<>$03 or j<>$37 or k<>$BC) xerror();
passed();
printf(layer, "TESTING GETHSC() AND SETHSC()");
sethsc(0,&$1357); hscrl0 = gethsc(0);
sethsc(1,&$2468); hscrl1 = gethsc(1);
//setdst(hscrl0); printf("%nHSCRL0=$%w, "); setdst(hscrl1); printf("HSCRL1=$%w%n");
if (>hscrl0<>$13 or <hscrl0<>$57) xerror();
if (>hscrl1<>$24 or <hscrl1<>$68) xerror();
passed();
printf(layer, "TESTING GETVSC() AND SETVSC()");
setvsc(0,&$9BDF); vscrl0 = getvsc(0);
setvsc(1,&$0ACE); vscrl1 = getvsc(1);
//setdst(vscrl0); printf("%nVSCRL0=$%w, "); setdst(hscrl1); printf("VSCRL1=$%w%n");
if (>vscrl0<>$9B or <vscrl0<>$DF) xerror();
if (>vscrl1<>$0A or <vscrl1<>$CE) xerror();
passed();
//putln("RESTORING LAYER REGISTERS");
setadr($1F, &$2000); setmem(@layer0, &layer0);
setadr($1F, &$3000); setmem(@layer1, &layer1);
goto exit;