2-18
The pin assignments for nibble mode parallel interface connector is as following:
Table 3. Pin Assignments For nibble mode Parallel Interface Connector
Pin SPP Mode Nibble Mode In/Out Function
1 Strobe HostClk In
A low on this line indicates that there are valid
data at the host. When this pin is de-asserted, the
+ve clock edge should be used to shift the data
into the device.
2-9 Data 0-7 Data 0-7 In Data Bus. Single-directional.
10 Ack PtrClk Out
A low on this line indicates that there are valid
data at the Device. When this pin is de-asserted,
the +ve clock edge should be used to shift the
data into the host.
11 Busy PtrBusy Out
When in reverse direction, a high indicates data,
while a low indicates a command cycle. In forward
direction, it functions as PtrBusy.
12
Paper Out /
End
AckDataReq Out
When low, device acknowledges reverse request.
13 Select X-Flag Out Extensibility flag
14 Auto Linefeed HostBusy In
When in forward direction, a high indicates data,
while a low indicates a command cycle. In reverse
direction, it functions as HostBusy.
15 No Defined NC N/A
16-17 Ground Ground GND Ground
18 Logic High High / Vcc Out
19-30 Ground Ground GND Ground
31 Initialize nInit In
A low indicates data in reverse direction
32 Error / Fault nDataAvail Out
A low set by the device indicates that the reverse
data is available
33-35 Ground Ground GND Ground
36 Select Printer 1284 Active In
A high indicates that host is in 1284 transfer
mode. Taken low to terminate.
To Next Page
Loading...
