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;
; PRBUSY.ASM
;
; from WSCUST13.ASM by Gerry Werth
;
; This routine worked with WS v3.30.
; -- I have no idea if it can be used on WS4 or even if it is needed
;
;----------------------------------------------------------
; The following is by Ted Warn, ROCC, as published in
; The Portable Companion, Oct 1983, p52, by John Dilday.
; Self patch for BIOS location by Gerry Werth.
;

PRBSY	lda	0002h		;Load  Hi Byte of BIOS in Accumulator
	sta	CLBZ+2		;Store Hi Byte of BIOS for Call
CLBZ	call	002Dh		;Call BIOS+2Dh subroutine
				;Upper address byte of BIOS is found at 0002h
			;( may look with WS226 INSTALL -- But DON'T CHANGE )
				;Lower address byte is 2Dh
	ana	a	; test for busy = FF
			;(compare to itself (test for zero and reset carry))
	rnz		; cond ret if not 00
			;(If nonzero then not busy so return with carry = 0)
	cmc		; comp carry flag to = 0
			;(Else A=0 so yes BUSY so return with carry = 1)
	ret		; ret from subroutine
	;
;
;	This routine assumes printer status routine at location 2d leaves the
;accumulator = 0 if printer is not busy.
;	In some versions of CP/M this printer status flag is reversed.  The
;conditional return may have to be changed from RNZ to RZ.
;
; End of Printer Busy Patch
	;
	;
;
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