Rockwell Automation T8xxx Trusted Communications Interface - Manual (Page 31)

Trusted
TM
Communication Interface T8151B
Issue 21 Apr 10 PD-T8151B 31
The following tables list the valid values for each of the control and status register types. In all cases
invalid values written to the control registers result in the inactive state being selected.
State Value Description
Inactive 0 Do not poll or ping the slave
Standby 1
Ping the slave to ensure communications are
possible
Active 2 Poll the slave for data
Table 9 Modbus Slave Control Register
State Value Description
Healthy 0
1. Slave is responding normally
2. Slave is set to inactive
Unavailable 1
1. Slave has failed to respond to a ping on a
link declared as standby.
2. Master is in error or is initialising
3. Master is set to inactive
Communications
Fail
2
Slave is being polled for data and not
responding
Slave Error 3 Illegal values are being requested from slave
Table 10 Modbus Slave Status Register