Section 5. Interface Specifications

PIN ASSIGNMENTS

 

 

RS232C Interface Signals

 

 

 

PIN

DIRECTION

SIGNAL DEFINITION

 

 

 

1

Reference

FG (Frame Ground)

 

 

 

2

To Host

TD (Transmit Data) - Data from the printer to the host computer.

 

 

Sends X-On/X-Off characters or status data (Bi-Directional

 

 

protocol).

 

 

 

3

To Printer

RD (Receive Data) - Data to the printer from the host computer.

 

 

 

4

To Host

RTS (Request to Send) - Used with Ready/Busy flow control to

 

 

indicate an error condition. RTS is high and remains high unless

 

 

the print head is open (in this case, RTS would return to the high

 

 

state after the print head is closed and the printer is placed back

 

 

on-line) or an error condition occurs during printing (e.g., ribbon

 

 

out, label out).

 

 

 

5

To Printer

CTS (Clear to Send) - When this line is high, the printer assumes

 

 

that data is ready to be transmitted. The printer will not receive

 

 

data when this line is low. If this line is not being used, it should be

 

 

tied high (to pin 4).

 

 

 

6

To Printer

DSR (Data Set Ready) - When this line is high, the printer will be

 

 

ready to receive data. This line must be high before data is

 

 

transmitted. If this line is not being used, it should be tied high (to

 

 

pin 20).

7

Reference

SG (Signal Ground)

20

To Host

DTR (Data Terminal Ready) - This signal applies to Ready/Busy

 

 

flow control. The printer is ready to receive data when this pin is

 

 

high. It goes low when the printer is off-line, either manually or due

 

 

to an error condition, and while printing in the Single Job Buffer

 

 

mode. It will also go low when the data in the buffer reaches the

 

 

Buffer Near Full level.

 

 

 

 

 

 

READY/BUSY FLOW CONTROL

Ready/Busy is the hardware flow control for the serial interface on the M-8400RV printer. By raising/lowering the voltage level on Pin 20 of the RS232 port, the printer notifies the host when it is ready to receive data. Pin 4 (RTS) and pin 20 (DTR) are the important signals on the printer for this method of flow control. The host must be capable of supporting this flow control method for it to function properly.

SATO M-8400RV

9001041 Rev. D

Page 5-4

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SATO M-8400RV manual RS232C Interface Signals, PIN Direction Signal Definition