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 ohms to ground.
Adaptable connector :57-30360 (Amphenol) or equivalent
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)
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
-
-
-
DATA
DATA ( n )
STROBE
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
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