User manual

Reference MVI56-HART ♦ ControlLogix Platform
User Manual HART Multi-drop Master Communication Module
Page 116 of 171 ProSoft Technology, Inc.
October 13, 2011
If the most-significant bit of the word contains "0", the most significant byte contains a
command error code. In this case, the least-significant byte contains device malfunction
information.
If this word value is "-1" (or 0xFFFF), it means that the command timed out.
Use the error codes returned for each command in the list to determine the success or
failure of the command. If the command fails, use the error code to determine the cause
of failure.
5.8.3 Protocol Error Codes
These are error codes that are part of the HART protocol. The standard HART error
codes are shown in the tables below:
Error Code Word
First Byte Second Byte
7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0
BIT 7 OF FIRST BYTE = 1
COMMUNICATION ERROR
FIRST BYTE
BIT 6 Parity Error
BIT 5 Overrun Error
BIT 4 Framing Error
BIT 3 Checksum Error
BIT 2 Reserved
BIT 1 RX Buffer Overflow
BIT 0 Undefined
SECOND BYTE
BIT 0 to BIT 7 All 0
BIT 7 OF FIRST BYTE = 0
COMMAND ERROR
FIRST BYTE
Bits 6 to 0 (not bit-mapped):
0 No Error
1 Undefined
2 Invalid Selection
3 Passed Parameter Too Large
4 Passed Parameter Too Small
5 Too Few Data Bytes Received
6 Transmitter-Specific Command Error
7 In Write-Protect Mode
8 to 15 Command Specific Errors (see Below)
16 Access Restricted
32 Device is Busy