Atari 400 Technical Reference Manual page 337

ERR LINE ADDR B1 B2 B3 B4 CASSET HANDLER
3/12
(DK1:CASCV)
PAGE 76
3307 · PAGE
3308
3309 SUBROUTINES
3310
3311 BEEP - GENERATE TONE ON KEYBOARD SPEAKER
3312 ON ENTRY A= FREG
3313
3314 F058
85 40 BEEP: STA FREG
3315 F05A A5 14 BEEP1 : LDA RTCLOK+2 iCURRENT CLOCK
3316 F05C 18 CLC
3317
· IF
PALFLG
3318 ADC #25
3319 · ENDIF
3320
· IF
PALFLG-1
3321 F05D
69 1E ADC
#30
i
1 SEC TONE
3322
· ENDIF
3323 F05F
AA TAX
3324
F060
A9 FF WFL: LDA
#$FF
3325 F062 8D 1F DO STA CONSOL iTURN ON SPEAKER
3326 F065 A9 00 LDA #0
3327 F067 AO FO LDY #$FO
3328 F069
88 DEY
3329 F06A DO FD BNE *-1
3330 F06C 8D 1F DO STA CONSOL iTURN OFF SPEAKER
3331 F06F AO FO LDY #$FO
3332 F071 88 DEY
3333 F072 DO FD BNE
*-1
3334 F074 E4 14 CPX RTCLOK+2
iSEE IF 1 SEC IS UP YET
3335 F076
DO E8 BNE WFL
3336 F078 C6 40 DEC FREG iCOUNT BEEPS
3337 F07A FO OB BEG WFAK
i
IF ALL DONE GO WAIT FOR KEY
3338 F07C 8A TXA
3339 F07D
18 CLC
3340
· IF
PALFLG
3341 ADC #8
3342
· ENDIF
3343
· IF
PALFLG-1
3344 F07E
69 OA ADC #10
3345
· ENDIF
3346 F080 AA TAX
3347 F081
E4 14 CPX RTCLOK+2
3348 F083
DO FC BNE
*-2
3349 F085 FO D3 BEG BEEP 1 iUNCOND GO BEEP AGIN
3350 F087 20 8C FO
WFAK: JSR WFAK1 iUSE SIMULATED "JMP (KGETCH)"
3351 F08A
98 TYA
3352 F08B 60 RTS
3353 F08C AD 25 E4 WFAKl : LDA KEYBDV+5
3354 F08F 48
PHA
3355
F090
AD 24 E4 LDA KEYBDV+4 iSIMULATE "JMP (KGETCH)"
3356 F093 48 PHA
3357 F094 60
RTS
3358
3359 SIOSB - CALL SIO ON SYSTEM BUFFER
3360