
PARALLEL PORT PIN SIGNALS
510
Parallel port pin signals
This table shows the parallel port’s connected pins; other pins are not connected.
Parallel port signals
Pin Signal mode names:
Compatibility/Nibble
Return
pin
Signal
source
Description
1 Busy/PtrBusy 19 Printer
■ C mode: Positive true = not ready for data
■ N mode: Data bits 3 then 7, then busy
status
2 Select/Xflag 20 Printer ■ C mode: Positive true = online
■ N mode: Data bits 1 then 5
3 nAck/PtrClk 21 Printer
■ C mode: Negative true = data transfer
acknowledge
■ N mode: Data qualifier
4 nFault/nDataAvail 22 Printer
■ C mode: Negative true = printer fault exists
that prevents printing
■ N mode: Negative low = data ready, then
data bits 0 then 4
5 PError/AckDataReq 23 Printer ■ C mode: Positive true = printer error exists,
such as media tray empty
■ N mode: Data bits 2 then 6
Komentáře k této Příručce