Arteche smART P500, Инструкция по эксплуатации

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6BFUNCTIONS IMPLEMENTED IN THE SMART P500
0BMODBUS RTU PROTOCOL
5.6.3. FUNCTION CODE 08 – DIAGNOSTICS
Function 08 offers several mechanisms that can be used to verify the operation of the
communication system between the master and the smART P500. This function uses a
two bytes sub-function code in the request to completely define the required function.
The sub-function codes implemented in the relay are shown in the following table:
Sub
function
Description
00 Return Query Data
10 Clear counters and diagnostic register
11 Return bus message count
12 Return bus communications error count
13 Return bus exception error count
14 Return slave message count
15 Return slave no response count
5.6.4. FUNCTION CODE 16 – WRITING OF VALUES
Using this function a set of values can be written in the memory of the smART P500 in a
single operation. The values to write are always 16 bits (2 bytes) in length and the most
significant byte is transmitted first. Up to 125 contiguous points can be written in a single
operation.
Only a small group of the available points can be written. See the memory map before
trying to write to a register. Some of the values that can be written have 32 or more bits.
In these cases, it requires all the points to be written in a single operation using this
function code. The smART P500 will reject partial writes to these points, except where
otherwise indicated.
5.6.5. EXCEPTION CODES
When an error is detected (different than a CRC error), the smART P500 generates a
response containing an exception code to inform the master. Generated responses are
the following: