mirror of
https://github.com/wwarthen/RomWBW.git
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38 lines
727 B
NASM
38 lines
727 B
NASM
;
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;======================================================================
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; I/O BIT DRIVER FOR CONSOLE BELL FOR SBC V2 USING BIT 0 OF RTC DRIVER
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;======================================================================
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;
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SPK_INIT:
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CALL NEWLINE ; FORMATTING
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PRTS("SPK: IO=0x$")
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LD A,DSRTC_BASE
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CALL PRTHEXBYTE
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CALL SPK_BEEP
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XOR A
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RET
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;
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SPK_BEEP:
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PUSH DE
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PUSH HL
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LD HL,400 ; CYCLES OF TONE
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;LD B,%00000100 ; D2 MAPPED TO Q0
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;LD A,DSRTC_RESET
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LD A,(RTCVAL) ; GET RTC PORT VALUE FROM SHADOW
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OR %00000100 ; D2 MAPPED TO Q0
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LD B,A
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SPK_BEEP1:
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LD A,B
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OUT (DSRTC_BASE),A
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XOR %00000100
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LD B,A
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LD DE,17
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CALL VDELAY
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DEC HL
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LD A,H
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OR L
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JR NZ,SPK_BEEP1
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POP HL
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POP DE
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RET
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