Tektronix Phaser 540 Plus User Manual page 161

The table shows the parallel port's connected pins. Other pins are not
connected.
Parallel port signal descriptions
Pin Signal mode names:
Compatibility/Nibble
1 Busy/PtrBusy
2 Select/Xflag
3 nAck/PtrClk
4
nFault/nDataAvail
5 PError/AckDataReq
6 Data 1
7 Data 2
8 Data 3
9 Data 4
10 Data 5
Return Signal Description
pin source
19 Printer C mode:
N mode:
20 Printer C mode:
N mode:
21 Printer C mode:
N mode:
22 Printer C mode:
N mode:
23 Printer C mode:
N mode:
24 Host C mode:
N mode:
25 Host C mode:
N mode:
26 Host C mode:
N mode:
27 Host C mode:
N mode:
28 Host C mode:
N mode:
A
Technical Notes
Positive true = not ready
for data
Data bits 3 then 7, then
busy status
Positive true = online
Data bits 1 then 5
Negative true = data
transfer acknowledge
Data qualifier
Negative true = printer
fault exists that prevents
printing
Negative low = data ready
then data bits 0 then 4
Positive true = printer
error exists, such as
media tray empty
Data bits 2 then 6
Positive true data input
Not used
Positive true data input
Not used
Positive true data input
Not used
Positive true data input
Not used
Positive true data input
Not used
A-11
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