Table 6 Serial Port S1/S2 Statistics (Left Side Of Display) - Honeywell 900 User Manual

Serial Port S1/S2
Item
Port Diagnostic
Port Status
Messages Received
Data Link Errors
Application Errors
Clear Statistics
Revision 9
May 2014

Table 6 Serial Port S1/S2 Statistics (left side of display)

Shows the overall condition of the Serial Port S1. See the list of Serial Port S1
diagnostic conditions in Table 7 on page 24.
This is the current status of the port. The possible status conditions are:
GOOD: the protocol is set to ELN.
REQUIRES SETUP: the protocol is set to one of the Modbus Slave protocols, and
the Slave Address is set to 255. Messages on the communication link are ignored
in this state.
OFFLINE: the protocol is set to one of the Modbus Slave protocols, and the Slave
Port Enable is set to DISABLE. Messages on the communication link are ignored
in this state.
ONLINE: the protocol is set to one of the Modbus Slave protocols, and the Slave
Port Enable is set to ENABLE. Messages on the communication link are being
processed in this state.
NO MODBUS SLAVE BLOCKS: the protocol is set to one of the Modbus Slave
protocols, but there are no Modbus slave function blocks present in the controller's
configuration.
PROGRAM MODE: the protocol is set to one of the Modbus Slave protocols, but
the controller is in Program Mode. The controller does not scan the slave devices in
this state.
ELN SLAVE: the protocol is set to one of the Modbus Slave protocols, but the
controller is in Program Locked Mode. The port automatically reverts to ELN
protocol and the controller becomes a slave device whenever the mode selection
switch is placed in the Program Locked position.
SCANNING SLAVES: the protocol is set to one of the Modbus Slave protocols, and
the controller is actively scanning the slave devices attached to the port.
The number of messages that were received and processed correctly.
The number of basic link-level errors detected by the controller. If the protocol is
Modbus Master, the errors may be due to a slave device that does not reply when it
is scanned. Refer to the section "Troubleshooting Data Link Errors" (page 35) for
more information.
The number of messages that were responded to with an exception code. For
example, application errors can be caused by (a) writing to a read-only register, (b)
accessing a register that is not supported by the slave device, or (c) using a
Modbus function code that is not supported by the slave device.
This item resets the message counters for this port back to zero (Messages
Received, Data Link Errors, and Application Errors). Note: the counters will only be
reset if the controller is in Run Mode.
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