Sensia CamCor, Protocol Manual

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Baud Rate SW3-1 Setting SW3-2 Setting
Do Not Set On On
Figure 1.1—Maintenance board switch locations and on/off positions
Standard Modbus Function Codes
The Modbus functions supported by CamCor Coriolis meters are as follows:
Function Code Description
03 (03H) Read Holding Registers
16 (10H) Preset Multiple Registers
Exception Response
If the device receives an unsupported function code in a query message, the device responds with an exception message.
For example, if the query message contains Function Code “11,” an unrecognized code, the function code on the
response message will be changed to the unexpected value code and “0x80,” or “0x91” in this case (original Function
Code + 80). The data value contains the exception code 0x02.
Slave Addresses
Allowed Slave Addresses
Slave devices are shipped from the factory with a slave address of “1.” Typically, each slave device should be assigned a
unique slave address. Allowed slave addresses range from 1 to 255. Slave Address “0” broadcasts messages to all slave
devices and is only available for Function Code 16. If the broadcast message contains valid data, the device is updated
and no response is sent to the host system. For information about invalid message handling, see Exception Response .
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Section 1 CamCor
™
Modbus Protocol