Micronics U1000MKII-FM, User Manual

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Micronics U1000MKII User Manual
Issue 3.1 July 19 Page 49
6.5.3 Modbus Error Messages (if Modbus fitted)
Test case
Transmitter
Address Command Start Register
Length
(no of registers)
CRC-16
[1 byte] [1 byte] [2 bytes] [2 bytes] [2 bytes]
No error 0x01 0x03 0x00 0x00 0x00 0x20 0x44 0x12
Incorrect function
request 0x01 0x0C 0x00 0x00 0x00 0x20 0x10 0x13
incorrect register
start 0x01 0x03 0x00 0xEF 0x00 0x20 0x75 0xE7
Incorrect register
length 0x01 0x03 0x00 0x12 0xFF 0x02 0x25 0xFE
slave is busy 0x01 0x03 0x00 0x00 0x00 0x20 0x44 0x12
incorrect CRC-16 0x01 0x03 0x00 0x20 0x00 0x20 0x44 0xFF
Receiver
Comments Address Command Error code CRC-16
[1 byte] [1 byte] [1 byte] [2 bytes]
0x01 0x03 None n/a n/a Example of a good message
0x01 0x8C 0x01 0x85 0x00 ILLEGAL FUNCTION - the only acceptable
command is 0x03
0x01 0x83 0x02 0xC0 0xF1 ILLEGAL DATA ADDRESS - incorrect
register start
0x01 0x83 0x03 0x01 0x31 ILLEGAL DATA VALUE - incorrect register
length
0x01 0x83 0x06 0xC1 0x32
SLAVE DEVICE BUSY
–
U1000 is busy
processing and is unable to respond
0x01 0x83 0x07 0x00 0xF2 CRC is incorrect
6.5.4 Flow Errors
A signal strength of less than 40% indicates poor set up of the instrument, and the installation
should be checked or possibly moved to a different site.
6.5.5 Flow Warnings
A signal strength of less than 40% indicates poor set up of the instrument, and the installation
should be checked or possibly moved to a different site. A negative flow is indicated by an”!” being
displayed on the top line instead of a “*”.