Pin Assignments; Ready/Busy Flow Control - SATO M-8400RV Operator And Technical Reference Manual

Section 5. Interface Specifications

PIN ASSIGNMENTS

PIN DIRECTION
1 Reference
2
3 To Printer
4
5 To Printer
6 To Printer
7 Reference
20

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 (
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
RS232C Interface Signals
FG (Frame Ground)
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).
RD (Receive Data) - Data to the printer from the host computer.
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).
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).
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).
SG (Signal Ground)
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.
9001041 Rev. D
SIGNAL DEFINITION
) and pin 20 ( ) are
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