TEC B-372-QP Manual page 20

(14) Input/Output Signals
Printer
(15) Connector Pin Assignment and Signal Description
Signal
Pin No.
Name

1 FG

2 RD



3 TD



4 CTS


5 RTS



6 DTR



7 SG

20 DSR

FG
TD
RD
RTS
CTS
DSR
SG
DTR
Function
Ground line for circuit protection
Line for data which the printer receives from the host.
Logic 1 is a Low level, while logic 0 is a High level.
It is in the Low (Mark) state when no transmission is in
progress.
Line for data which the printer sends to the host.
Logic 1 is a Low level, while logic 0 is a High level.
It is in the Low (Mark) state when no transmission is in
progress.
Input signal from the host.
For the printer to send data, the signal must be "High"
level.
Output signal to the host.
It indicates that there is data to be output to the host.
After the power is turned on, it is always at "High" level.
Output signal to the host.
It indicates the ready state for the received data.
It is at "Low" level when the receive buffer is near full,
and at "High" level when near empty.
Ground line for all data and control signals.
Input signal from the host.
For the printer to receive data, it must be at "High"
level.
- 4 -
Host CPU
Signal Direction
← Host
Printer →
← Host
Printer →
Printer →
← Host