Epson Stylus Color 670 Service Manual

EPSON Stylus Color 670 Revision A
Product Description Interface 20
1.3.4 Miscellanea
1.3.4.1 Receive Data Buffer Full Operation
Generally, hosts abandon data transfer to peripherals when a peripheral
is in the busy state for dozens of seconds continuously. To prevent hosts
from this kind of time-out, the printer receives data very slowly, several
bytes per minute, even if the printer is in busy state. This slowdown is
started when the rest of the input buffer becomes several hundreds of
bytes. Finally, the printer is in the busy state continuously when the input
buffer is full. USB and IEEE-1284.4 on the parallel interface do not require
this function.
1.3.4.2 Interface Selection
The printer has 2 built-in interfaces; the USB and parallel interface. These
interfaces are selected automatically.
AUTOMATIC SELECTION
In this automatic interface selection mode, when the printer is initialized
to the idle state scanning which interface receives data when it is
powered on. Then the interface that receives data first is selected. When
the host stops data transfer and the printer is in the stand-by state for the
seconds, the printer is returned to the idle state. As long as the host sends
data or the printer interface is in the busy state, the selected interface is
let as it is.
INTERFACE STATE AND INTERFACE SELECTION
When the parallel interface is not selected, the interface got into the busy
state. When the printer is initialized or returned to the idle state, the
parallel interface got into the ready state. Caution that the interrupt signal
such as the -INIT signal on the parallel interface is not effective while that
interface is not selected.
1.3.4.3 IEEE 1284.4 protocol
The packet protocol described by IEEE1284. 4 standard allows a device to
carry on multiple exchanges or conversations which contain data and / or
control information with another device at the same time across a single
point-to-point link. The protocol is not, however, a device control
language. It does provide basic transport-level flow control and
multiplexing services. The multiplexed logical channels are independent
of each other and blocking of one has no effect on the others. The
protocol operates over IEEE 1284.
o Automatic selection
An initial state is compatible interface and starts IEEE12844
communication when magic strings (1284.4 synchronous commands)
are received.
o On
An initial state is IEEE1284.4 communication and data that received it
by the time it is able to take synchronization by magic string (1284.4
synchronous commands) is discarded.
o Off
An initial state is compatible interface and never starts IEEE1284.
communication even if magic strings (1284.4 synchronous
commands) are received.

Epson Stylus Color 670 Specifications

General

Brand	Epson
Model	Stylus Color 670
Category	Printer
Language	English