Automating Measurements 6-9
Controlling Peripherals
Using the Parallel Port
Reading from the Parallel Port
The parallel port has five TTL input signals, normally used for
determining the printer's status, which can be read. The signals and the
corresponding data bits and pins are shown in the following table:
Table 6-4 Parallel Port Inputs
Your custom interface circuit can drive these signals, and they can be
read using the following commands.
SCPI commands:
OUTPUT @Rfna;"DIAG:PORT:READ? 15,10"
ENTER @Rfna;Parallel_in
IBASIC command:
Parallel_in = READIO(15,10)
Pin Bit Name
10 D0 Acknowledge
11 D1 Busy
12 D2 Out of Paper
13 D3 On Line
15 D4 Printer Error