User Manual

Compact IO™ Isolated HART Analog Input Module
U ser 's M a n u a l 0 300 21 5- 03 R ev. A
7-38
The command status, the second byte in the reply packet for the module specific
command, can return three different responses, SUCCESS, RUNNING and DEAD.
These responses echo the state of the module at the time the command is sent. The
conditions for each response are as follows:
SUCCESS will be sent ba ck under the following conditions:
•
Command and HART Cha nnel number are bot h valid .
•
HART channel is enabled.
•
Command handle matches currently act ive handle a nd the hand le is in the
HOLD state.
•
After replying with a SUCCESS, the handle will beco me inactive, thus allo wing
for next pass-through or host i nitiated upd a te o f device i n for mation.
RUNNING will be sent back under the following conditions:
•
Command and HART Cha nnel number are bot h valid .
•
HART channel is enabled.
•
Command handle matches curr entl y ac tive handle.
•
HART channel is already in the state of handling a pass-through command.
Reply will be sent back without additional events triggered.
DEAD will be sent back if any of the follow ing conditions are true:
•
Command or HART Chan nel number is invalid.
•
HART channel is not enabled.
•
HART communication has not been establis hed , meaning that the 5-b yte unique
address has not been determined yet.
•
All other conditioned not generating RUNNING o r SUCCESS. Examples are:
inva l id handle, handle ti med out, c hannel unde r device informat ion gat hering,
and etc.
The following ladder demonstrates how to perform the pass-through request and query
process.
Figure 7-10a (Pass-Through Ladder)