Xerox 820-II Word Processing Applications And Reference Manual page 214

PRINTER PATCH AREA
0783 00 00 00
0786 00
0787
7F
DB 0,0,0 ;RESERVED
;
; *****
PRINTER COMMUNICATIONS PROTOCOL
****
;
; APPLICABLE IF CSWTCH=O, 1, OR 2.
; APPLICABLE FOR ALL POSMTH VALUES.
;
; THREE BUFFER FULL PROTOCOLS ARE SUPPORTED:
;
; NO PROTOCOL: (PROTCL=O): NO PROTOCOL EXECUTED IN
; XEROX WP: USE IF NONE REQUIRED OR IF HANDLED
; ELSEWHERE, EG IN OPERATING SYSTEM OR IN USER
; DRIVER ROUTINES.
;
;ETX/ACK PROTOCOL (PROTCL=I): WS TRANSMITS "ETX" AT END
;OF STRING OF CHARACTERS, PRINTER RESPONDS WITH
;"ACK" WHEN ALL OF THESE CHARACTERS HA VE BEEN
;PRINTED. DRIVER MUST BE ABLE TO INPUT CHARACTERS.
;
; XON/XOFF PROTOCOL (PROTCL=2): PRINTER
SENDS "X OFF" WHEN WS SHOULD STOP SENDING,
"XON" WHEN TRANSMISSION SHOULD BE RESUMED.
DRIVER MUST BE ABLE TO INPUT CHARACTERS.
;
PROTCL: DB 0 ;O=NO PRINTER BUFFER FULL PROTOCOL
;1=ETX/ACK PROTOCOL. SET EAKBSZ BELOW 1
;2=XON/XOFF PROTOCOL
; USE 0 FOR MOST TTY -LIKE PRINTERS AND FOR SERIAL
; DAISY PRINTERS INTERFACED AT 300 BAUD OR SLOWER.
; FOR DIABLO AND QUME AT 1200 BAUD, USE 1.
; FOR NEC AT 1200 BAUD, USE 1 OR 2 AND CONFIGURE THE
; PRINTER APPROPRIATELY, OR USE 0 & CABLE ADAPTER.
EAKBSZ: DB 127 ;ETX/ACK MESSAGE LENGTH (1/2 PRINTER'S
;BUFFER SIZE), APPLICABLE ONLY IF ;PROTOCL=I,
;AUTOMATICALLY PATCHED FOR DAISY; PRINTERS.
0788 00 00 DB 0,0 ;RESERVED FOR EXPANSION
078A 00 00 00 00 DB 0,0,0,0 ;RESER VED FOR EXPANSION
078E ALABEL EQU $;ASSEMBLER SHOULD PRINT 78E
END ;NEXT MODULE LOADS AT 790H
REFERENCE
13-50