Communications Manual Rev 3.10 Software Versions 3.xx
003R-618-310
Page 17
4.2. Error Handling
If a command cannot be processed, the indicator returns an error code. Typical
errors include:
• Register not implemented on indicator
• Register value out of range
• Command not implemented for register
An error response is indicated by setting the Error bit in the Address Field of the
reply.
The message returned by the indicator in response to an error will be of the form:
Address
Field
Command
Field
Register Id Error Code
zz mm rrrr “:” wwwww
An error code will consist of a hexadecimal value representing the specific error
code.
Note: When an error occurs, the most significant bit is 1 and other bits indicate the
specific problem. More than one error bit may set if more than one error is present.
Refer to Error Codes page 38.
For example, attempting to read the type of the register with Id = 0000
H
(not
implemented) will return:
C1010000:A000
which is interpreted as:
C1
H
= 1100 0001
b
• Response to a command
• Error
• Unit responding is address 01
H
01
H
= REG_READ_TYPE (the command that was sent).
0000
H
= Register Id.
A000
H
= 1010 0000 0000 0000
b
is the error code which is interpreted as
• REG_ERR_ERROR = 8000
H
(most significant bit set)
• REG_NOT_IMPLEMENTED = 4000
H