Interfaces; Parallel Interface (Forward Channel) - Epson Stylus COLOR 800 Service Manual

1.5 Interfaces

The EPSON Stylus COLOR 800 is equipped with two interfaces: parallel and Mac serial interface, and a
card slot for an optional Type-B interface. This section provides information on each interface.

1.5.1 Parallel Interface (Forward Channel)

Transmission Mode
‰Synchronization
‰Handshaking
‰Signal Level
Table 1-14. Signal Level for TTL-Compatible IEEE-1284 Level 1 Device
Parameter
VOH*
VOL*
IOH*
IOL*
CO
VIH
VIL
IIH
IIL
CI
Notes: * A LOW logic level on the Logic H signal line is as follows:
2.0 V or less when the printer is powered off.
3.0 V or more when the printer is powered on.
The receiver provides an impedance equivalent to 7.5K ohms to ground.
Adaptable Connector
The BUSY signal is set HIGH before setting either /ERROR LOW or PE HIGH, and held HIGH until all
these signals return to an inactive state. The BUSY signal is HIGH in the following cases:
‰During data entry.
‰When the input data buffer is full.
‰While /INIT signal is at a LOW level or during hardware initialization.
‰During a printer error condition (See the /ERROR signal).
‰During test printing.
‰When the printer is in default setting mode.
‰When the parallel interface is not selected.
Rev. A
8-bit parallel, IEEE-P1284 compatibility mode
/STROBE pulse
BUSY and /ACKNLG signal
TTL compatible level (IEEE-P1284 Level 1 device)
Refer to Table 1-15.
Minimum
—
–0.5 V
—
—
—
—
0.8 V
—
—
—
57-30360 (Amphenol) or equivalent
Maximum Condition
5.5 V
—
0.32 mA VOH = 2.4 V
12 mA VOL = 0.4 V
50 pF
2.0 V
—
0.32 mA VIH = 2.0 V
12 mA VIL = 0.8 V
60 pF
Product Description
1-13