Programming Considerations; Communication Rate; Modem Operation; Modem Concept - Omega DPF700 User Manual

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8.6 PROGRAMMING CONSIDERATIONS

8.6.1 Communication Rate

If possible, use 9600 baud for communications instead of 1200. 9600 baud has a faster reading
rate and less time is spent communicating.
The table below details measurement and setup time:
Measurements (9 Characters)
Setup data (43 Characters)

8.6.2 Modem Operation

You may connect the meter to a freestanding modem, such as the Hayes Smartmodem 1200, to
transmit and receive data over phone lines. A typical controller would be an IBM PC with a Hayes
Smartmodem 1200B plug-in modem.
COMPUTER
Use a 1200 baud rate to receive measurement and setup data to be sent from the computer to
the meter. Connect an auto answering modem to the meter to gather data from a remote location
upon demand. If you send a command to the meter at 1200 baud while the
meter's active memor y is programmed for 9600 baud, the meter will
automatically switch to 1200 baud. This prevents the modem application from
being disabled when a setup parameter of 9600 baud is accidentally sent to
the meter.
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PTION
Table 8-5. Baud Rate Information
MODEM
Figure 8-14. Modem Concept
9600 Baud 1200 Baud
9.4 msec 75 msec
45.8 msec 360 msec
MODEM METER