Ready/Busy Flow Control - SATO M-8485Se Operator And Technical Reference Manual

Section 6. Interface Specifications
PIN DIRECTION
1 Reference
2 To Host
3 To Printer
4 To Host
5 To Printer
6 To Printer
7 Reference
20 To Host
Cable Requirements
DB9 DB25
1 1
2 3
3 2
8 5
7 4
4 20
6 6
5 7

READY/BUSY FLOW CONTROL

Ready/Busy is the hardware flow control method for the serial interface on the Se
printers. By raising/lowering the voltage level on Pin 20 of the RS232C port, the
printer notifies the host when it is ready to receive data. Pin 4 (RTS) and pin 20
Page 6-6
RS232C Interface Signals
FG (Frame Ground)
TD (Transmit Data) - Data from the printer to the host computer.
Sends X-On/X-Off characters or status data (Bi-Directional
protocols).
RD (Receive Data) - Data to the printer from the host computer.
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)
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.
HOST INTERCONNECTION
FG
RD
TD
CTS
RTS
DTR
DSR*
SG
PN 9001073 Rev C
SIGNAL DEFINITION
1 FG (Frame Ground)
2. TD (Transmit Data)
3 RD (Receive Data)
4 RTS (Request to Send)
5 CTS (Clear to Send)
6 DSR (Data Set Ready)
20 DTR (Data Terminal Ready)
7 SG (Signal Ground)
PRINTER
SATO "Se" Print Engines