Interfaces; Parallel Interface; Forward Channel Specifications - Epson Stylus COLOR 1520 Service Manual

1.3 Interfaces

1.3.1 Parallel Interface

1.3.1.1 Forward Channel Specifications

Transmission mode


Synchronization


Handshaking


Signal level
Table 1-15. Signal level of TTL Compatible (IEEE-1284 level 1 device)
Parameter
VOH*
VOL*
IOH*
IOL*
CO
VIH
VIL
IIH
IIL
CI
Note) * : A low logic level on the Logic H signal 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 shall provide an impedance equivalent to 7.5 K ohm top 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 the inactive state.
The BUSY signal is at high level in the following cases:

During data entry (see Figure 1-8. Data Transmission Timing below.)

When the input data buffer is full

While /INIT signal is at low level or during hardware initialization

During a printer error condition (See /ERROR signal)

During test printing

When the printer is in default setting mode

When the parallel interface is not selected
The ERROR signal is at low level when one of the following errors has occurred:

Printer hardware error (fatal error)

Paper-out error

Paper-jam error

Ink-out error
The PE signal is high level during paper-out error.
Rev. A
:8 bit parallel , IEEE-P1284 compatibility mode
:/STROBE pulse
:BUSY and /ACKNLG signal
:TTL compatible level (IEEE-P1284 Level 1 device)
Minimum
-
-0.5 V
-
-
-
-
0.8 V
-
-
-
:57-30360 (Amphenol) or equivalent
DATA
DATA (n)
STORBE
0.5 us (min.)
0.5 us (min.)
BUSY
ACKNLG
Figure 1-8. Data Transmission Timing
Maximum
5.5 V
-
0.32 mA
12 mA
50 pf
2.0 V
-
0.32 mA
12 mA
60 pf
DATA (n+1)
0.5 us (min.)
0 (min.)
0 (min.)
5 us (type.)
0 (min.)
Product Description
Condition
VOH = 2.4 V
VOL = 0.4 V
VIH = 2.0 V
VIL = 0.8 V
1-15