TallyGenicom 2440 User Guide

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Serial interface (option)
Interfaces
B-10
Serial Interface Timings
Ready/Busy
1. Data received when DSR is low is considered invalid and will be discarded. 
2. BUSY LOW (DTR) is dropped to indicate to the host that the receive buffer is full.
20
DTR
(Data Terminal Ready)
If user selects RTS as Busy line, this line will be set 
high and will remain high after the serial interface 
finishes its Reset.
If user selects DTR as Busy line, this line will be set 
high after the serial interface finishes its Reset 
sequence. However if Ready/busy handshake pro-
tocol is selected, this line is used to indicate to PC 
whether or not Printer is ready to receive any more 
data.
INIT
RTS
BUSY
(DTR)
DSR
Receive Data
Valid
Receive Data
1
2