Controlling Peripherals; Using The Parallel Port - HP 8712C User Manual

Controlling Peripherals

The analyzer lets you access its rear panel interface ports from your
measurement control program. Using this capability, you can communicate
with peripherals such as material handlers, custom DUT interface circuits,
external switch boxes, and printers.
Communication with the DIN KEYBOARD interface, the USER TTL, and
LIMIT TEST TTL connectors is described in detail in the earlier section titled
"Operator Interaction." This section will focus on use of the Centronics
parallel port and the RS-232 serial port.
The analyzer's parallel port can be used as an 8-bit TTL output port and as a
be read or used as bidirectional I/O lines. The parallel port does not support
the IEEE-1284-defined Extended Capabilities Port (ECP) Mode or Enhanced
Parallel Port (EPP) Mode.
The outputs signals are driven by standard TTL drivers. They should be
buffered for heavy duty applications, to avoid damaging the analyzer. The
inputs are standard TTL inputs, designed to accept signals in the OV to 5V
range.
The analyzer provides two ways to access the parallel port. You can use the
SCPI commands
OUTPUT BRfna;"DIAG:PORT:WRITE <port>,<register>,<data>
and
OUTPUT QRfna;"DIAG:PORT:READ? <port>,<register>
ENTER @Rfna;Data
or you can use IBASIC and its READ10 and WRITE10 commands. See the
following tables for more information.
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