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PRINTER PATCH AREA
071A
071B
071C
071D
071E
0720
0723
0724
0725
0726
0727
00
B7
C9
5F
OE 05
*****
PRINTER DRIVERS PER SE
*****
; THERE ARE FIVE DRIVERS, CORRESPONDING TO
; CSWTCH (PREVIOUS PAGE) = 00, 01, 02, 03, 04.
;
; EACH OF THE DRIVERS HAS THREE ENTRIES:
;
1.
BUSY STATUS ENTRY. RETURNS CY=1 IF
PRINTER IS NOT READY. IF UNIMPLEMENTED,
RETURN CY =0. HA VBSY SHOULD BE 0 IF
UNIMPLEMENTED AND FF
IF IMPLEMENTED.
2.
SEND CHARACTER (A REGISTER) ENTRY.
3.
INPUT A CHAR TO A, OR RETURN CY=1 IF NO
INPUT CHARACTER READY. THIS ENTRY IS USED
ONLY FOR ETX/ ACK AND XON/XOFF
BUFFER FULL PROTOCOLS IMPLEMENTED WITHIN
EDITOR (SEE "PROTCL" BELOW).
; THESE ROUTINES MAY CLOBBER ALL REGISTERS.
;
;PRINTER DRIVER TO OUTPUT TO CP/M LIST
;DE VICE. ONLY CALLED IF CSWITCH=OO.
LIBSY:
;BUSY TEST ENTRY - BUSY TEST MAY BE
;ADDED HERE IF YOUR OPERATING SYSTEM
;ALLOWS DETERMINING WHETHER PRINTER
;IS READY. PATCH HAVBSY TO FF IF USED.
NOP
ORA A
;RETURN CY=O TO SAY
RET
; •• NOT BUSY.
LISEND: ;OUTPUT CHARACTER (A) TO LIST DEVICE
MOV E,A
;CHARACTER IN E FOR CP/M
M VI C, LISTF;FUNCTION
II
IN C
CD 0005
CALLBDOS ;CALLSYSTEM
B7
C9
00
37
C9
ORA A
;CLEAR CY FLAG
RET
;RETURN TO CALLER
LISINP: ;INPUT CHARACTER TO (A) OR RETURN CY=l
;IF NONE. THIS FUNCTION IS NOT SUPPLIED
;BY OPERATING SYSTEM, USER MUST SUPPLY
;SUBROUTINE IF ETX/ACK OR XON/XOFF
;PROTOCOL IS TO BE USED.
NOP
STC
;IF NO ROUTINE INSTALLED, SAY
RET
; •• NO CHARACTER READY.
REFERENCE
13-45
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