Parallel Interface - Citizen OPTICAL MOUSE User Manual

Parallel Interface

Specifications
Transmission mode 8-bit parallel data
Receive buffer size 16kB
Transmission modes Compatible mode
It is an asynchronous forward direction of the byte width
(from host to printer) channel, and the interface line of
the data is operated in accordance with signal line
definitions of Centronics.
NIBBLE mode
Nibble mode is asynchronous reverse channel
communication with data transmission controlled by the
host computer. In reverse channel transmission, the data is
nibble transmitted in two parts using four status lines (Fault,
Select, PE, and Busy). And nibble mode can be used along
with compatible mode to send data in two directions.
ECP mode
ECP mode permits bi-directional asynchronous data
transmission, and thanks to its interlock handshake, it does
not require the timing necessary with compatible mode.
Signal level IEEE1284 standard
Signal line and pin assignment table
Pin No. Signal name I/O
1 *STROBE Input
2-9 DATA1-8 Input
10 *ACKNLG Output 8-bit data request signal
1 1 BUSY Output Signal specifying printer busy
12 PERROR Output Signal specifying media out
13 SELECT Output Signal specifying if the printer is on-line (printing
14 AUTOFD Input
15 NC ---
16 GND ---
17 FGND ---
18 P.L.H Output Peripheral logic high (pull up to +5V at 1.2kΩ)
19-30 GND ---
31 *INIT Input
32 *FAULT Output Signal specifying printer error
33-35 NC ---
36 SELECTIN Input
47
Function
Strobe signal to read in 8-bit data
8-bit parallel signal
enabled) or off-line (pausing)
Invalid (ignored)
Not used
Signal ground
Frame ground
Ground for twisted pair return
Printer reset
Not used
Invalid (ignored)
Appendixes
Interfaces