Parallel Interface (Reserve Channel) - Epson Stylus PHOTO 1270 Service Manual

EPSON Stylus PHOTO 870/1270

1.3.2 Parallel Interface (Reserve Channel)

"
Transmission mode: IEEE-1284 nibble mode
"
Adaptable connector See forward channel.
"
Synchronization: Refer to the IEEE-1284 specification.
Pin No.
1
2-9
10
11
12
13
14
31
32
36
18
35
17
16,33, 19-30
15,34
NOTE: In/Out refers to the direction of signal flow from the printer's point of view.
PRODUCT DESCRIPTIONS
Table 1-14. Connector Pin Assignment and Signals
Return
Signal Name In/Out
GND Pin
HostClk 19 In
DATA0-7 20-27 In
PtrClk 28 Out
PtrBusy / DataBit-
29 Out
3,7
AckDataReq /
28 Out
DataBit-2,6
Xflag / DataBit-1,5 28 Out
HostBusy 30 In
-INIT 30 In
-DataAvail /
29 Out
DataBit-0,4
1284-Active 30 In
Logic-H - Out
+5V - Out
Chassis GND - -
GND - -
NC - -
"
Handshaking:
"
Data trans. timing:
"
Signal level:
Functional Description
Host clock signal.
The DATA0 through DATA7 signals represent data bits 0 to 7,
respectively. Each signal is at high level when data is logical 1
and low level when data is logical 0. These signals are used to
transfer the 1284 extensibility request values to the printer.
Printer clock signal.
Printer busy signal and reverse channel transfer data bit 3 or
7.
Acknowledge data request signal and reverse channel
transfer data bit 2 or 6.
X-flag signal and reverse channel transfer data bit 1 or 5.
Host busy signal.
Not used.
Data available signal and reverse channel transfer data bit 0
or 4.
1284 active signal.
Pulled up to +5V via 3.9K ohm resistor.
Pulled up to +5V via 3.3K ohm resistor.
Chassis GND
Signal GND
Not connected
Interface
Refer to the IEEE-1284 specification.
Refer to the IEEE-1284 specification.
IEEE-1284 level 1 device (See forward
channel.)
Revision B
24