Chapter 5 Remote Interface Reference

Modem Communications

Modem Communications

This section gives details on communicating with the instrument from a remote PC using a modem. To communicate over the phone lines, you must have a PC and two modems. One modem is connected to

your PC (xvyz

) and the other is connected to the HP 34970A

(zz yz

). The steps below show how to set up a typical modem.

1. Connect the remote modem to your local PC.

2. Run the Windows hzv

or Uv

program to configure

the modem. These programs can be found in the Nxxz

group.

3.Set the baud rate using the Terminal program to the same value used for the HP 34970A. For more information on setting the instrument’s baud rate, refer to “Remote Interface Configuration” on page 152.

4.Configure the remote modem for auto answer, disable command echo, and disable result codes. Save these settings as the active profile.

For example, when using a Practical Peripherals PM14400FXMT modem, the command string is “AT&F1S0=1EQ1&W”, where:

AT

Set the baud rate and configure the modem to expect more commands.

&F1

Place the modem in its factory configuration, which is compatible

 

with most IBM-compatible PCs.

S0=1

Set to auto answer after one ring.

E

Disable error codes.

Q1

Disable result codes.

&W

Store settings for power-on profile.

 

 

5.Configure the HP 34970A for the “Modem” flow control mode

(for more information, see “Flow Control Selection” on page 153).

6.Remove the remote modem from the PC. Connect the remote modem to the HP 34970A using the RS-232 cable supplied (if you ordered the internal DMM) and modem adapter (HP part number 5181-6642). The modem adapter is available in the HP 34399A Adapter kit.

7.After turning on the remote modem, you should notice that the AA (auto answer) light is on. When you turn on the HP 34970A, you should notice that the TR (instrument ready) light is on.

8.Connect the remote modem to the phone line. From the local modem, dial up the remote modem using HP BenchLink Data Logger or another software application.

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Image 272
HP 34970A manual Modem Communications, Zz yz, For more information, see Flow Control Selection on, S0=1