Serial Interface; Optional Interface - Epson DFX-8500 Service Manual

SERIAL INTERFACE

Synchronization:


Signal level (ELA-232D):
MARK (logical 1):
SPACE (logical 0):


Word length:
Start bit:
Data bit:
Parity bit:
Stop bit:


Baud rate:


Handshaking:
DTR=MARK, X-OFF:
DTR=SPACE, X-ON:
Note: The DTR signal MARK, X-OFF (DC3, 13h) is transmitted when the input buffer reaches 256 bytes.
The DTR signal SPACE, X-ON (DC1, 11h) is transmitted when the input buffer falls below 256 bytes.


Error handling:


Connector:


Connector pin assignment and signals:
Table 1-14. Signal and Connector Pin Assignment (EIA-232D)
Pin No. Signal
Name
2 TXD
20 DTR
11 REV
4 RTS
3 RXD
7 Signal GND
1 Chassis
GND
Other NC
* From the printer's point of view.

OPTIONAL INTERFACE

Type-B and Type-B (level 2) optional interfaces are available. (See Table 1-1.)
Asynchronous
–3 V to –25 V
+3 V to +25 V
1 bit
8 bit
Odd, Even, None, or Ignore
1 bit or more
2400, 4800, 9600 or 19200 bps
DTR signal or X-ON / X-OFF
Indicates that the printer cannot receive data.
Indicates that the printer is ready to receive data.
When a parity error is detected, the received byte is changed to the "*"
character code and a string of asterisks is printed. Overrun and framing
errors are ignored.
25-pin sub-miniature D-shell connector (female)
See Table 1-14.
I/O*
O Transmits data.
O Indicates whether the printer is ready to receive data.
O Connected directly to the DTR signal.
O Request to Send: always set to SPACE when the printer is on.
Pulled up to +12 V via a 4.7 kΩ resistor.
I Receive data.
- Signal GND.
- Chassis GND.
- Not used. Not connected.
PRODUCT DESCRIPTION
Description
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