Interface Specifications; Parallel Interface (Forward Channel) - Epson Stylus COLOR 440 Service Manual

EPSON Stylus COLOR 440, 640, and 740

1.3 Interface Specifications

A parallel interface is standard on all three printers.

1.3.1 Parallel Interface (Forward Channel)

Transmission mode 8-bit parallel, IEEE-1284 compatibility mode
Synchronization
STROBE pulse
Handshaking BUSY and ACKLG signals
Signal level
TTL-compatible level
Adaptable connector 57-30360 (Amphenol) or equivalent
The BUSY signal is set high before setting either ERROR low or PE
high, and remains high until these signals return to their inactive state.
The BUSY signal is HIGH at these times:

During data entry

When the input data buffer is full

When the INIT signal is LOW, or during hardware initialization

When there is a printer error (See ERROR signal)
The ERROR signal is LOW when the printer is in one of the following
states.

Printer hardware error (fatal error)

Paper-out error

Paper-jam error

Ink-out error
The PE signal is HIGH during a paper-out error.
Table 1-10 on the following page shows the signal and connector pin
assignments for the parallel interface. With these signals, a twisted pair
line is used and the return side is connected to the GND signal.
NOTE: The forward channel is the mode used to send ordinary data,
such as when a print command is sent from the computer to
the printer.
Chapter 1 Product Description
17