Diagnostics, 0X08; Diagnostics Register Interpretation - Grundfos CIM 200 Functional Profile And User Manual

12.6 Diagnostics, 0x08

Diagnostics is only supported by Modbus RTU.
This function provides a test for checking the communication
system between the master and the Grundfos slave. It contains a
single-byte subcode to identify the test to be performed.
The following subcodes are supported:
Subcode Name
Return query data.
Data in this request are to be echoed in the
0x00 response. The response must be identical to the
request, so this function is often used to verify
Modbus communication.
Restart communications.
0x01 All communication counters are cleared, and the
device is restarted.
Return diagnostics register.
0x02 Returns the 16-bit diagnostics register. See section
12.7 Diagnostics register
Force listen only.
Forces the device into listen-only mode. This
effectively mutes the device, making it unable to
0x04 communicate on the network. To bring the device
back to normal mode, a "Restart communications"
command, code 0x08, subcode 0x01, must be
issued.
Clear counters and diagnostics register.
0x0A Clears all counters and the diagnostics register.
These are also cleared on power-up and restart.
Return bus message count.
0x0B Returns the number of messages detected by the
slave.
Return bus CRC error count.
0x0C
Returns the number of CRC errors in the slave.
Return bus exception count.
0x0D Returns the number of Modbus exception responses
that the slave has transmitted.
Return slave message count.
0x0E Returns the number of messages that the slave has
processed.
Return slave no response count.
0x0F Returns the number of messages for which the
slave has sent no response.
interpretation.

12.7 Diagnostics register interpretation

The diagnostics register is interpreted as follows:
Bit Description
0 Communication failure, with the Grundfos product.
1 RESERVED
2 Grundfos product is not supported.
Modbus address offset is different from default value, i.e.
3
it differs from 0.
4 Using software-defined Modbus transmission speed.
5 RESERVED
6 RESERVED
7 RESERVED
8 RESERVED
9 RESERVED
10 RESERVED
11 RESERVED
12 RESERVED
13 RESERVED
14 RESERVED
15 RESERVED
A bit value of 1 means that the statement in the description is
true, unless otherwise specified. The diagnostics register is read
using function code 0x08 and subcode 0x02.
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