ProSoft Technology 5202-DFNT-MCM4 - Manual (Page 37)

Serial Port Modbus Error and Status Data MCM ♦ ProLinx Gateway
Driver Manual Modbus Master/Slave
ProSoft Technology, Inc.
Page 37 of 80
October 16, 2009
Port 0 Command Error List Layout
The addresses listed are for Port 0 only; but the format is the same for each port.
The start address for each port is given in the previous section, Master Port:
Command List Errors (page 36).
Internal Database
Address (Example)
Offset Description
4410 0 Command #0 Error Status
4411 1 Command #1 Error Status
4412 2 Command #2 Error Status
4413 3 Command #3 Error Status
4414 4 Command #4 Error Status
... ... ...
... ... ...
... ... ...
4507 97 Command #97 Error Status
4508 98 Command #98 Error Status
4509 99 Command #99 Error Status
Note that the values in the Command Error List tables are initialized to zero (0) at
power-up, cold boot, and warm boot. If a command executes successfully, the
value in the associated register will remain at zero (0), indicating no command
error was detected. Any non-zero value in this table indicates the corresponding
command experienced an error. The Error Code (page 39) shown will provide
valuable troubleshooting information.
The data in this table is dynamic. It is updated each time a command is
executed. Therefore, if the command fails once and succeeds on the next
attempt, the Error Code from the previously failed attempt will be replace with
zero and lost. Error Codes are not archived in the gateway's database. To see if
the port has experienced an error since the most recent restart and what the
most recently occurring error was, if any, you can check the Last Error/Index
(page 34).
4.2.4 Master Port: Modbus Slave List Status
The slave status list contains the current poll status of each slave device on a
Master port. Slaves attached to a Master port can have one of three states.
0 The slave has not defined in the command list for the Master port and will not be polled
from the Command List.
1 The slave is configured to be polled by the Master port and the most recent
communication attempt was successful.
2 The Master port has failed to communicate with the slave device. Communication with
the slave is suspended for a user defined period based on the scanning of the
command list.