Epson Stylus Pro XL, Service Manual

Page: 14 / 127

Table 1-9 shows the connector pin assignments and signal functions of the 8-bit parallel interface.
Table 1-9. Signal and Connector Pin Assignments for Parallel Interface
Pin No. Signal Name I/O* Description
1 STROBE I
The STROBE pulse is used to read data from the host
computer. The pulse width must be 0.5
µ
s or more. Normally,
it is HIGH, and data is latched with the rising edge of this
signal.
2-9 DATA 1-8 I
DATA 1-8 are parallel data bits. When one of these signals is
HIGH, the data bit is 1; when LOW, the data bit is 0. The
most significant bit (MSB) is DATA 8. The signal state must
be maintained for 0.5
µ
s on either side of the STROBE
signal’s active edge.
10 ACKNLG O
ACKNLG is an acknowledge pulse with a width of
approximately 10
µ
s. This signal goes LOW upon the
completion of data reception to indicate that the printer is
ready to receive further data.
11 BUSY O
The BUSY signal informs the host computer of the printer’s
status. When this signal is HIGH, the printer cannot accept
any more data.
12 PE O
This signal indicates whether paper is available in the printer
or not. A HIGH level indicates no paper.
13 SLCT O
Pulled up to +5 V through a 1.0 K
Ω
resistor in the printer.
14
AFXT I
If this signal is set to LOW, the printer automatically performs
one line feed upon receipt of a CR (carriage return) code. The
status of this signal is checked only at power on and
initialization.
31 INIT I
If this signal goes LOW, the printer is initialized. The pulse
width of this signal must be 50
µ
s or more.
32 ERROR O
This signal goes LOW if the printer has a fatal error or runs
out of paper.
35 +5 V —
Pulled up to +5 V through 1.0 K
Ω
resistor in the printer.
17 CHASSIS — Chassis ground.
16 GND — Signal ground.
19-30 — — —
33,36 — — Not used.
15,18,34 — — —
* The I/O column indicates the direction of the signal as viewed from the printer.
Stylus Pro XL Product Description
Rev.A 1-11