HP 8712C, Руководство пользователя, Страница: 340 / 559

Automating Measurements
Controlling Peripherals
Like the parallel port, the serial port can also be accessed
using
SCPI
and commands.
‘lb write a byte with a value of 52 decimal (34 hex, 0011 0100 binary) to the
serial port, use one of the following commands:
OUTPUT
lb read a byte from the serial port, use the following commands:
OUTPUT
ENTER
you are using you can simply use the statement:
S e r i a l - i n =
For general purpose l/O, the parallel port is much easier to interface to than
the serial port. lb interface to the serial port, a Universal Asynchronous
Receiver Transmitter (UART) is typically used to decode the
signals.
Most are designed to be used with microprocessors.
The advantage of the serial port is that it can operate over long distances, up
to 30 meters using the
standard. Its disadvantage is its slow speed;
limited to 19200 bits/second.
Before using the serial port, you must select the baud rate and handshake
style using the SCPI commands:
One type of application for the serial port would be to use it for data logging
to a remote computer. After each device is measured, an program
could use the command shown above to send a brief summary
of the measurement result, such as a filter’s 3 bandwidth and its serial
number, to the remote computer. A program on the remote computer would
monitor the serial port and read the incoming data and archive it to hard disk
or the network.
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