General Description
‘ Manual
Note 1: ( )
indicates an
signal, which is
Note 2:
‘US”,
and
states can be selected through
Note3: Although the
and
used
for
mode if selected through
Note4: SD+, SD-:
Serial ASCII data output from the printer.
HIGH level; when SD+ voltage is higher than SD-voltage.
LOW level; when SD+ voltage is less than SD-voltage.
Logic O is “SPACE” and logic 1 is “MARK” state must be maintained between
transmitted character codes.
Serial ASCII data input from the computer.
HIGH level; when
voltage is higher than
voltage.
LOW level; when
voltage is less than
voltage.
Logic O is “SPACE” and logic 1 is “MARK” state must be maintained between
transmitted character codes.
Handshaking
When the
vacant area
for data the input buffer drops to 256 bytes, the printer outputs an
cede or sets the
to LOW, indicating that the printer cannot receive more data.
Once
the vacant area for data
buffer recovers to
bytes, the printer outputs an X-ON code
or sets the
to
indicating that the
printer is again ready to receive data.
Protocol
There are two types of protocols, as listed below, and each of them can be designated by
independently.
■
protocol
is used to execute the
control protocol. The
signal is set to HIGH when
the printer is ready to receive data, and to LOW when conditions indicate an error or that the
receiving buffer is full.
When the error is cleared and the printer returns to on-line mode, the signal returns to HIGH.
When
is used to set the
OFF,
is always set HIGH. The printer transmits
only when
is at the HIGH level (DSR is always considered HIGH when the
setting for
is OFF).
transmission is independent of the
state.
■
X-ON/X-OFF
is used to execute the X-ON/X-OFF protocol. The X-OFF
code is output if status
.
indicates an error, and the printer warns the host to stop data transmission within 128 characters.
No further X-OFF codes are sent in response to additional data received from the host after the
X-OFF code has been sent once. The
(DCl) code is output after renditions given in the
error are cleared.
When the remaining capacity of the receive buffer reaches 256 characters, X-OFF
is output
once. It is sent only once, even if there are multiple errors. The printer goes on line automatically at
power on, and outputs an X-ON code. Transmission of
codes can be defined by
1-18
Rev.
Summary of Contents for EPL-9000
Page 1: ...EPSON TERMINAL PRINTER SERVICE MANUAL EPSON ...
Page 8: ...REVISION SHEET Revision Date Rev 5 1994 Revision Page I issue vii ...
Page 117: ...Disassembly and Service Figure 3 50 Removing the ROS Unit 3 32 Rev ...
Page 118: ...Chapter 4 Adjustments Adjustment is required in this product ...
Page 160: ...Service Manual Appendix 0 c 1 R13 J Figure A 6 C135 MAIN Board Component Layout Rear Side Rev ...
Page 161: ......
Page 162: ...EPSON ...
