PCE Instruments PCE-P18 - Description of the MODBUS Protocol Implementation; Description of the Functions Used

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6.2. Description of the MODBUS protocol implementation
The implemented protocol is compliant with the PI-MBUS-300
Rev G specification of Modicon.
Set of parameters of the P18D transducer serial link in the MODBUS
protocol:
Transducer address 1..247.
Baud rate: 4800, 9600, 19200, 38400, 57600, 115200 [b/s].
Operating mode: RTU frame format: 8N2, 8E1, 8O1, 8N1.
Maximum response time: 500 ms
Configuration of the serial link parameters consists of determining
the baud rate, the device address and the format of the transmission
mode - protocol.
Caution: Each transmitter connected to the communication network must:
have a unique address, different from the addresses of other devi-
ces connected to the network.
Identical baud rate and type of a transmission mode
6.3 Description of the functions used
Following functions of the MODBUS protocol have been implemented
in P18D transducers:
03 (03h) – readout of registers group,
04 (04h) – readout of input registers group,
06 (06h) – single register writing,
16 (10h) – registers group writing,
17 (11h) – slave device identification.
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