Epson AcuLaser C8500, Service Manual

Page: 49 / 570

EPSON AcuLaser C8500 Revision C
PRODUCT DESCRIPTIONS Interface Specifications 1-29
Figure 1-12. Data Transmission Timing
Table 1-22. Data Transmission Timing
Min. Typ. Max
(1) Data hold setup 0.5 us
(2) Data hold 0.5 us
(3) Strobe pulse 0.5 us
(4) BUSY to STRBX 0 us
(5) STROB to BUSY 0.5 us
(6) BUSY to STRBX 0 us
(7) ACKX pulse width 0.5 us 1 us*
(8) ACKX to BUSY 0 s
(9) BUSY to PE or ERRX 2 ms*
(10) PE or ERRX to BUSY 2 ms*
(11) Power on to signal output valid 05 s
(12) PE or ERRX to ACKX 2 ms*
(13) STRBX to ACKX 0 s*
1 3 2
6 8
VALID VALID
7
6 8
VALID VALID
D ATA
STR BX
BU SY
AC KX
Table 1-23. Centronics Parallel Interface Pin Assignment
Pin # Signal Names I/O Descriptions
1 STRBX I
Latch pulse used to read data. DATA is valid
when the signal is LOW.
2-9 DATA 1-8 I DATA 8 is MSB and DATA 1 is LSB.
10 ACKNLGX O
An acknowledge pulse to the host that indicates
the data from the host computer has been
received.
11 BUSY O
HIGH status indicates the printer is not ready to
accept data.
12 PE O
Indicates paper empty status in paper tray or
cassette selected.
13 SELOT O Always HIGH.
14 AUTOX I
When the signal is LOW, the printer automatically
feeds a line as “CR” is input. The “CR” is detected
when the printer is turned on or the interface
selection is switched from the optional I/F to
parallel I/F.
15 NC - Not used.
16 GND - Ground level for the twisted pair return.
17 CG -
Connected to the printer chassis. The printer
chassis GND and the signal GND are connected
each other.
18 NC - Not used.
19-30 GND - Ground level for the twisted pair return.
31 INITX I
When the signal is LOW, the STRBX signal is
ignored.
32 ERRX O
The signal is LOW when the printer is in the
following condition:
1) User maintenance is required. 2) Service
maintenance is required. 3) Another type of error
has occurred. 4) The printer is off line.
33 GND - Ground level for the twisted pair return.