Replica 1 TE Users Manual
© Briel Computers 2007 page
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Appendix C: Woz Monitor listing
FF00: D8
RESET
CLD
Clear decimal arithmetic mode.
FF01: 58
CLI
FF02: A0 7F
LDY #$7F
Mask for DSP data direction register.
FF04: 8C 12 D0
STY DSP
Set it up.
FF07: A9 A7
LDA #$A7
KBD and DSP control register mask.
FF09: 8D 11 D0
STA KBD CR
Enable interrupts, set CA1, CB1, for
FF0C: 8D 13 D0
STA DSP CR
positive edge sense/output mode.
FF0F: C9 DF
NOTCR
CMP #$DF
“_”?
FF11: F0 13
BEQ BACKSPACE Yes.
FF13: C9 9B
CMP #$9B
ESC?
FF15: F0 03
BEQ ESCAPE
Yes.
FF17: C8
INY
Advance text index.
FF18: 10 0F
BPL NEXTCHAR Auto ESC if > 127.
FF1A: A9 DC
ESCAPE
LDA #$DC
“\”.
FF1C: 20 EF FF
JSR ECHO
Output it.
FF1F: A9 8D
GETLINE
LDA #$8D
CR.
FF21: 20 EF FF
JSR ECHO
Output it.
FF24: A0 01
LDY #$01
Initialize text index.
FF26: 88
BACKSPACE
DEY
Back up text index.
FF27: 30 F6
BMI GETLINE
Beyond start of line, reinitialize.
FF29: AD 11 D0
NEXTCHAR
LDA KBD CR
Key ready?
FF2C: 10 FB
BPL NEXTCHAR Loop until ready.
FF2E: AD 10 D0
LDA KBD
Load character. B7 should be ‘1’.
FF31: 99 00 02
STA IN,Y
Add to text buffer.
FF34: 20 EF FF
JSR ECHO
Display character.
FF37: C9 8D
CMP #$8D
CR?
FF39: D0 D4
BNE NOTCR
No.
FF3B: A0 FF
LDY #$FF
Reset text index.
FF3D: A9 00
LDA #$00
For XAM mode.
FF3F: AA
TAX
0->X.
FF40: 0A
SETSTOR
ASL
Leaves $7B if setting STOR mode.
FF41: 85 2B
SETMODE
STA MODE
$00=XAM $7B=STOR $AE=BLOK XAM
FF43: C8
BLSKIP
INY
Advance text index.
FF44: B9 00 02
NEXT ITEM
LDA IN,Y
Get character.
FF47: C9 8D
CMP #$8D
CR?
FF49: F0 D4
BEQ GETLINE
Yes, done this line.
FF4B: C9 AE
CMP #$AE
“.”?
FF4D: 90 F4
BCC BLSKIP
Skip delimiter.
FF4F: F0 F0
BEQ GETLINE
Yes. Set STOR mode.
FF51: C9 BA
CMP #$BA
“:”?
FF53: F0 EB
BEQ SETSTOR
Yes. Set STOR mode.
FF55: C9 D2
CMP #$D2
“R”?
FF57: F0 3B
BEQ RUN
Yes. Run user program.
FF59: 86 28
STX L
$00-> L.
FF5B: 86 29
STX H
and H.
FF5D: 84 2A
STY YSAV
Save Y for comparison.