Stella H/W Monitor Source

[Curt Vendel]

;

;

; NEW MONITOR

;

;

;

; DAVE CRANE FEB 7 1978

;

; LARRY WAGNER COPY PROM TO RAM DEC 18 1978

;

;

;

; PIA AND TIMER (6532) LOCATIONS

 

SWCHA = $280 P0,P1 JOYSTICKS **A=B DUE TO WIRING IN STELLAX BOARD**

SWCHB = $280 CONSOLE SWITCHES

CTLSWA = $281

CTLSWB = $281

INTIM = $284 ;INTERVAL TIMER IN

TIM8T = $295 ;TIMER 8T WRITE OUT

TIM64T = $296 ;TIMER 64T WRITE OUT

TIM1KT = $297

; STELLA (TIA) REGISTER ADDRESSES

 

VSYNC = $00 BIT 1 VERTICAL SYNC SET-CLR

VBLANK = $01 BIT 1 VERTICAL BLANK SET-CLR

WSYNC = $02 STROBE WAIT FOR HORIZ BLANK

RSYNC = $03 STROBE RESET HORIZ SYNC COUNTER

NUSIZ0 = $04 BITS 54 210 NUMBER-SIZE PLAYER/MISSILE 0

NUSIZ1 = $05 BITS 54 210 NUMBER-SIZE PLAYER/MISSILE 1

COLUP0 = $06 BITS 7654321 COLOR(4)-LUM(3) PLAYER 0

COLUP1 = $07 BITS 7654321 COLOR(4)-LUM(3) PLAYER 1

COLUPF = $08 BITS 7654321 COLOR(4)-LUM(3) PLAYFIELD

COLUBK = $09 BITS 7654321 COLOR(4)-LUM(3) BACKGROUND

CTRLPF = $0A BITS 7 54 210 PLAYFIELD CONTROL

REFP0 = $0B BIT 3 REFLECT PLAYER 0

REFP1 = $0C BIT 3 REFLECT PLAYER 1

PF0 = $0D BITS 7654 PLAYFIELD REG BYTE 0

PF1 = $0E BITS ALL PLAYFIELD REG BYTE 1

PF2 = $0F BITS ALL PLAYFIELD REG BYTE 2

RESP0 = $10 STROBE RESET PLAYER 0

RESP1 = $11 STROBE RESET PLAYER 1

RESM0 = $12 STROBE RESET MISSILE 0

RESM1 = $13 STROBE RESET MISSILE 1

RESBL = $14 STROBE RESET BALL

AUDC0 = $15 BITS 3210 AUDIO CONTROL 0

AUDC1 = $16 BITS 3210 AUDIO CONTROL 1

AUDF0 = $17 BITS 3210 AUDIO FREQUENCY 0

AUDF1 = $18 BITS 3210 AUDIO FREQUENCY 1

AUDV0 = $19 BITS 3210 AUDIO VOLUME 0

AUDV1 = $1A BITS 3210 AUDIO VOLUME 1

GRP0 = $1B BITS ALL GRAPHICS FOR PLAYER 0

GRP1 = $1C BITS ALL GRAPHICS FOR PLAYER 1

ENAM0 = $1D BIT 1 ENABLE MISSILE 0

ENAM1 = $1E BIT 1 ENABLE MISSILE 1

ENABL = $1F BIT 1 ENABLE BALL

HMP0 = $20 BITS 7654 HORIZ MOTION PLAYER 0

HMP1 = $21 BITS 7654 HORIZ MOTION PLAYER 1

.PAGE

HMM0 = $22 BITS 7654 HORIZ MOTION MISSILE 0

HMM1 = $23 BITS 7654 HORIZ MOTION MISSILE 1

HMBL = $24 BITS 7654 HORIZ MOTION BALL

VDELP0 = $25 BIT 0 VERTICAL DELAY PLAYER 0

VDELP1 = $26 BIT 0 VERTICAL DELAY PLAYER 1

VDELBL = $27 BIT 0 VERTICAL DELAY BALL

RESMP0 = $28 BIT 1 RESET MISSILE TO PLAYER 0

RESMP1 = $29 BIT 1 RESET MISSILE TO PLAYER 1

HMOVE = $2A STROBE ACT ON HORIZ MOTION

HMCLR = $2B STROBE CLEAR ALL HM REGISTERS

CXCLR = $2C STROBE CLEAR COLLISION LATCHES

; READ ADDRESSES - BITS 7 & 6 ONLY

CXM0P = $30

CXM1P = $31

CXP0FB = $32

CXP1FB = $33

CXM0FB = $34

CXM1FB = $35

CXBLPF = $36

CXPPMM = $37

INPT0 = $38

INPT1 = $39

INPT2 = $3A

INPT3 = $3B

INPT4 = $3C

INPT5 = $3D

.PAGE

; RAM PAGE ZERO DEFINITIONS

*=$A0

POINTL *=*+1 LOW MEMORY POINTER

POINTH *=*+1 HIGH MEMORY POINTER

*=$E800

USERAC *=*+1 AC

USERX *=*+1 X REG

USERY *=*+1 Y REG

USERSP *=*+1 STACK POINTER

PCL *=*+1 PC LOW

PCH *=*+1 PC HIGH

STATUS *=*+1 STATUS REG

CHKSUM *=*+1

CHKHI *=*+1

ERRFLG *=*+1

ERR0 *=*+1

ERR1 *=*+1

CNTR *=*+1 OUTPUT COUNTER

INL *=*+1 LOW INPUT BUFFER

INH *=*+1 HIGH INPUT BUFFER

TEMP2 *=*+1

TMPX *=*+1

TMPX1 *=*+1

TMPX2 *=*+1

CHAR *=*+1

CNTL30 *=*+1

CNTH30 *=*+1

TIMH *=*+1

TEMP *=*+1

TEMP1 *=*+1

OFFSET *=*+1 OFFSET FOR MOVING ZERO PAGE

.PAGE

*=$E400

;

;

CTLCON=$282 CONTROL CONSOLE SWITCHES

SWHCON=$283 DATA CONSOLE SWITCHES

;

RST LDA #$04 SET PROM/RAM SWITCH

STA CTLCON TO RAM

LDX #$FF

STX SWHCON

STX USERSP

TXS

JMP START4

START STA USERAC (BREAK ENTRY POINT)

PLA

STA STATUS

SAVE1 PLA (JSR ENTRY POINT)

STA PCL

PLA

STA PCH

SAVE2 STY USERY

STX USERX

TSX

STX USERSP

JSR SWAP

LDA PCL

STA POINTL

LDA PCH

STA POINTH

CLD

JMP BREAK

START4 CLD

SEI

JSR SWAP

START2 LDA #0

STA ERRFLG

START3 LDX #$FF

TXS

LDA #1

STA CNTH30 SET 300 BAUD

LDA #$1C

STA CNTL30

LDA #$3F

STA CTLSWB

PROMPT LDA ERRFLG

BEQ PROMPA

JMP ENDLD2

PROMPA JSR CRLF

PROMP1 LDA #$3E '>'

JSR OUTCH

LDA #0 CLEAR INPUT BUFFER

STA INH

STA INL

STA ERRFLG

GETHEX JSR GETBYT

BEQ GETHEX

CMP #$20 SPACE

BEQ PROC1

CMP #$2E '.'

BEQ PROC2

CMP #$D CARRIAGE RETURN

BEQ PROC3

CMP #$A LINE FEED

BEQ PROC4

CMP #$52 'R' RAM TESTER

BNE GETHE1

JMP RAMTST

GETHE1 CMP #$48 'H'

BEQ HIBAUD

CMP #$4D 'M' TO MOVE PROM TO RAM

BNE GETHE2

JMP COPY

GETHE2 CMP #$4C 'L'

BEQ LOBAU1

CMP #$47 'G'

BEQ PROC5

CMP #$7F RUBOUT

BEQ START2

JMP GETHEX IGNORE ILLEGAL CHARACTERS

PROC1 JSR OPEN OPEN AND DISPLAY CURRENT CELL

JSR TESTLM TEST FOR E0-FF LIMITS

JMP SHOW

PROC2 LDY #0

JSR TESTLM GO GET OFFSET

JSR ADDOFF

LDA INL

STA (POINTL),Y STORE DATA

LDA TEMP2 RESTORE POINTH

STA POINTH

PROC3 JSR INCPT NEXT CELL

JMP SHOW

PROC4 SEC

LDA POINTL DECREMENT POINTER

SBC #1

STA POINTL

BCS PROC4A

DEC POINTH

PROC4A JMP SHOW

PROC5 LDX #$A0 RESTORE RAM

LDA POINTL

STA PCL

LDA POINTH

STA PCH

PROC5A LDA $E800,X

STA $00,X

INX

BNE PROC5A

GOEXEC LDX USERSP

TXS

LDA PCH

PHA

LDA PCL

PHA

LDA STATUS

PHA

LDA #0 RESTORE JOYSTICK PORT TO READ ONLY

STA CTLSWA

LDX USERX

LDY USERY

LDA USERAC

RTI

HIBAUD JSR CRLF

LDA #$44

STA CNTL30

LDA #0

STA CNTH30

JMP LOBAUD

LOBAU1 JSR CRLF

LOBAUD LDY #0

JSR GETCH LOADER ROUTINE

CMP #$3B SEMICOLON

BNE LOBAUD WAIT FOR SEMICOLON

LOAD1 LDA #0 CLR CHKSUM

STA CHKSUM

STA CHKHI

JSR GETTST

TAX PUT BYTE COUNT IN X

BEQ ENDLD IF ZERO BYTE COUNT, GO END

JSR CHK ADD TO CHKSUM

;

JSR GETTST GET HIGH ADDRESS

STA POINTH

JSR CHK

JSR GETTST GET LOW ADDRESS

STA POINTL

JSR CHK

;

LOAD2 JSR GETTST GET DATA

STA (POINTL),Y

JSR CHK

JSR INCPT

LOAD3 DEX

BNE LOAD2

;

LOAD4 JSR GETTST COMPARE CHKSUM

CMP CHKHI

JSR ERROR1

JSR GETTST

CMP CHKSUM

JSR ERROR1

JMP LOBAUD

;

;

GETTST JSR GETBYT

BEQ GETTS1

LDA #1 BIT 0 IS ILLEGAL CHARACTER

ERROR2 STA ERRFLG

LDA POINTL SAVE ERROR ADDRESS

STA ERR0

LDA POINTH

STA ERR1

PLA

PLA

JMP LOBAUD

GETTS1 LDA INL

ERROR3 RTS

ERROR1 BEQ ERROR3

LDA ERRFLG

ORA #2 BIT 1 IS CHECKSUM ERROR

JMP ERROR2

;

ENDLD LDX #2 READ REMAINING ZEROS

ENDLD1 JSR GETTST

DEX

BPL ENDLD1

ENDLD2 JSR CRLF

LDX #9 PRINT ERROR MESSAGE

ENDLD3 LDA MSGTBL,X

JSR OUTCH

DEX

BPL ENDLD3

LDA ERRFLG

JSR PRTBYT

JSR OUTSP

LDA ERR1

JSR PRTBYT

LDA ERR0

JSR PRTBYT

JMP START2

;

;

SHOW JSR CRLF

JSR PRTPNT

JSR OUTSP

JSR ADDOFF

LDY #0

LDA (POINTL),Y

JSR PRTBYT

LDA TEMP2

STA POINTH

JSR OUTSP

JMP PROMP1

;

;

; BEGIN SUBROUTINES

;

.PAGE

;

; ADD OFFSET TO POINTH

;

ADDOFF CLC ADD IT IN

LDA POINTH

STA TEMP2

ADC OFFSET

STA POINTH

RTS

;

; GET CHARACTER

;

GETCH STX TMPX SAVE X

LDY #$7

GET1 BIT SWCHA

BMI GET1 WAIT FOR START BIT

JSR DELAY DELAY 1 BIT

GET5 JSR DEHALF DELAY 1/2 BIT

GET2 LDA SWCHA GET 8 BITS

AND #$80 MASK OFF LOW ORDER BITS

LSR CHAR SHIFT RIGHT CHARACTER

ORA CHAR

STA CHAR

JSR DELAY DELAY 1 BIT TIME

DEY

BNE GET2 GET NEXT CHAR

JSR DEHALF EXIT THIS RTN

;

LDX TMPX

LDA CHAR

LSR A

GET6 RTS

;

;

; PRINT CARRIAGE RETURN AND LINE FEED

;

CRLF STX TMPX1

LDA #$0D CR

JSR OUTCH

LDA #$0A LF

JSR OUTCH

LDX #5 PRINT NULLS

CRLF1 LDA #0

JSR OUTCH

DEX

BPL CRLF1

LDX TMPX1

RTS

;

; PRINT CHARACTER

; X IS PRESERVED Y = $FF

; OUTSP PRINTS 1 SPACE

;

OUTSP LDA #$20

OUTCH STA CHAR

STX TMPX2

LDA #$3F MAKE JOYSTICK PORT READ/WRITE

STA CTLSWB

OUT3 JSR DELAY

LDA SWCHB START BIT

AND #$FE

STA SWCHB

JSR DELAY

LDY #$8

OUT1 LDA SWCHB DATA BIT

AND #$FE

LSR CHAR

ADC #0

STA SWCHB

JSR DELAY

DEY

BNE OUT1

LDA SWCHB STOP BIT

ORA #$1

STA SWCHB

JSR DELAY STOP BIT

LDX TMPX2

LDA #0

STA CTLSWA

RTS

;

; DELAY 1 BIT TIME

;

DELAY LDA CNTH30

STA TIMH

LDA CNTL30

DE2 SEC

DE4 SBC #$1

BCS DE3

DEC TIMH

DE3 LDX TIMH

BPL DE2

RTS

;

; DELAY 1/2 BIT TIME

;

DEHALF LDA CNTH30

STA TIMH

LDA CNTL30

LSR A

LSR TIMH

BCC DE2

ORA #$80

BCS DE4

;

;

;

;

; SUB TO PRINT POINTL,POINTH

;

PRTPNT LDA POINTH

JSR PRTBYT

LDA POINTL

JSR PRTBYT

RTS

;

;

; PRINT 1 HEX BYTE AS TWO ASCII CHARACTERS

;

PRTBYT STA TEMP

LSR A

LSR A

LSR A

LSR A

JSR HEXTA CONVERT TO HEX AND PRINT

LDA TEMP GET BOTTOM HALF

JSR HEXTA

LDA TEMP RESTORE ACCUMULATOR

RTS

;

HEXTA AND #$F MASK

CMP #$A

CLC

BMI HEXTA1

ADC #7 ALPHA HEX

HEXTA1 ADC #$30 DEC HEX

JMP OUTCH

;

;

; SUBROUTINE TO INCREMENT MEMORY POINTER

;

INCPT INC POINTL

BNE INCPT2

INC POINTH

INCPT2 RTS

;

;

; GET 2 HEX CHARACTERS AND PACK THEM INTO

; THE INPUT BUFFER. X IS PRESERVED. ANY NON-HEX

; CHARACTER IS RETURNED IN THE AC. ANY ENTRY

; BETWEEN 0 AND F INCLUSIVE CAUSES A 0 RETURN IN THE AC.

;

GETBYT JSR GETCH

JSR PACK

BNE GETBY1 RETURN IF NON-HEX

JSR GETCH IF HEX, GET SECOND DIGIT

JSR PACK

GETBY1 RTS

;

;

; SHIFT AC INTO INPUT BUFFER

;

PACK CMP #$30 CHECK FOR HEX

BMI UPDAT2

CMP #$47 NOT HEX EXIT

BPL UPDAT2

HEXNUM CMP #$40 CONVERT TO HEX

BMI UPDATE

HEXALP CLC

ADC #$9

UPDATE ROL A

ROL A

ROL A

ROL A

LDY #4 SHIFT INTO BUFFER

UPDAT1 ROL A

ROL INL

ROL INH

DEY

BNE UPDAT1

LDA #0 RETURN 0 IF HEX

UPDAT2 CMP #0 RESTORE FLAGS

RTS

;

;

; OPEN CELL BY MOVING INPUT BUFFER INTO POINTER

;

OPEN LDA INL

STA POINTL

LDA INH

STA POINTH

RTS

;

;

;

; COMPUTE CHKSUM

;

CHK CLC

ADC CHKSUM

STA CHKSUM

LDA CHKHI

ADC #0

STA CHKHI

RTS

;

;

; TEST LIMITS. TEST FOR E0-FF, IF SO, OFFSET=$FC

;

TESTLM LDA #0

STA OFFSET

LDA POINTH

BNE TESTL1

LDA POINTL

CMP #$A0

BCC TESTL1 BRANCH IF POINTH.LT.$E0

LDA #$E8

STA OFFSET

TESTL1 RTS

;

SWAP LDX #$A0 SAVE 80-FF AT E880-E8FF

START1 LDA $00,X

STA $E800,X

INX

BNE START1

RTS

;

;

; PRINT BYTE FOLLOWED BY A SPACE

;

PBYTSP JSR PRTBYT

JMP OUTSP

;

;

;

;

;

;

; BL : R O R R E BL

MSGTBL .BYTE $07,$20,$3A,$20,$52,$4F,$52,$52,$45,$07

.BYTE "PS SP A Y X CP"

;

;

;

; BREAK DISPLAY

;

BREAK JSR CRLF

LDX #$12

BREAK1 LDA MSGTBL+10,X

JSR OUTCH

DEX

BPL BREAK1

JSR CRLF

LDA PCH

JSR PRTBYT

LDA PCL

JSR PBYTSP

LDA USERX

JSR PBYTSP

LDA USERY

JSR PBYTSP

LDA USERAC

JSR PBYTSP

LDA STATUS

JSR PBYTSP

LDA USERSP

JSR PRTBYT

JMP START4

;

;

;

; RAM TESTER: TEST RAM FROM POINTL,H TO INL,H

; REMOVED TO ALLOW COPY

;

RAMTST JMP PROMPT STUB UNTIL MORE ROOM

;

; COPY PROM TO RAM

;

COPY LDA #$04

STA CTLCON

LDA #$E8

STA POINTH

LDA #$00

STA POINTL

TAY

TAX

HOW STX SWHCON

LDA (POINTL),Y

LDX #$FF

STX SWHCON

STA (POINTL),Y

INC POINTL

LDX #$00

CPX POINTL

BNE HOW

INC POINTH

CPX POINTH

BNE HOW

JMP RST

;

;

;

;

;

;

;

;

;

*=$E7FC

.WORD RST

.WORD START

;

;

.END

[Bruce Tomlin]

Interesting. A joystick-serial monitor, but he used the RIOT timer instead of VSYNC for bit timing.

 

1978, huh? I'm pretty sure that predates the MAX-232 chip by a few years.

[djmips]

Interesting.  A joystick-serial monitor, but he used the RIOT timer instead of VSYNC for bit timing.

 

1978, huh?  I'm pretty sure that predates the MAX-232 chip by a few years.

929908[/snapback]

 

So this is an RS-232 compliant monitor. Hmmm seems like that would have been useful for debugging back in the day. Do you remember the 1488 and 1489?, those were ubiquitous before the MAX-232 but they required +/- voltages.

 

I've got a tube of MAX-232's, maybe I should see if I can get something to show up on HyperTerm.

[djmips]

Here's a DASM formatted version that builds.

 

Note, that the source as it is written uses 26 bytes of RAM at $E800

monitor.zip