Source Accesses Of Omron Plc Driver

The OMRON NSB X-Link driver supports three possible source accesses. The first source defines a local (internal) address that allows any device on the OMRON network to write the data to the X-Link. This type of source is ideal for data that changes infrequently, but must be forwarded immediately, such as errors or exceptions. Programming must be provided on the remote device to update the data when necessary.

The second type of source supported by the OMRON driver is an X-Link initiated read. This source defines an external address that the X-Link uses to read the data from a remote node on the network. This access also requires you to specify when to read the data. This type of data source does not require any programming in the remote node, but the X-Link generates extra network traffic to poll the data.

The third type of source supported by the OMRON driver is the diagnostic counters stored in the driver. This access allows an offset to be specified which indicates the number of bytes to skip from the beginning of the diagnostic counters.

Destination Accesses
The OMRON driver supports two possible destination accesses.
The first destination defines an internal (local) address that allows any device on the OMRON network to read the data from the X-Link. This type of destination allows a PLC to read back the data it has written. You must provide programming on the remote device to initiate the read.

The second type of destination access supported by the OMRON driver is an X-Link initiated writes. This destination defines an external address that the X-Link uses to write the data to a remote node on the network. This access also requires you to specify when to write the data. This type of data destination does not require any programming in the remote node and can avoid wasting network bandwidth that would be consumed by having the PLC poll the data.

Status Counters
The OMRON driver maintains several counters for logging events and errors. Each is one byte in length. The Status menu of the X-Link configuration software allows you to monitor these counters. As well, the status counters can be accessed as a data source for mappings, using the corresponding offsets.

The following lists the status counters and their offsets.
Offset 0;
Status Counter: Msgs_commands_sent
Significance: Total number of X-Link generated OMRON

Offset 1;
Status Counter: Msgs_replies_rx
Significance: Total number of OMRON replies (responses)

Offset 2;
Status Counter: Msgs_unsol_cmd_rx
Significance: Total number of unsolicited OMRON

Offset 3;
Status Counter: Msgs_replies_sent
Significance: Total number of OMRON replies sent by the driver

Offset 4;
Status Counter: Messages aborted
Significance: Number of the X-Link messages aborted by the kernel

Offset 5;
Status Counter: X-Links failures alloc
Significance: Number of X-Links failures in memory

Offset 6;
Status Counter: Send interrupts
Significance: Total count of hardware send interrupts generated by the Sysmac Link NSB card

Offset 7;
Status Counter: Receive interrupts
Significance: Total count of hardware interrupts generated by the card on receive OMRON messages (commands or replies)

Offset 8;
Status Counter: Time interrupts
Significance: Total count of hardware interrupts generated by the card on asking time to the X-Link

Offset 9;
Status Counter: Master Node Number
Significance: Node number of the polling unit on the local SYSMAC L

Offset 10;
Status Counter: Number of active nodes
Significance: Number of active nodes on the local SYSMAC LINK OMRON network

Offset 11;
Status Counter: Max node heard
Significance: Maximum node number heard by the OMRON NSB card on the local SYSMAC LINK OMRON network

Offset 12 + node number;
Status Counter: Node Status
Significance: Table with the status of each node on the local SYSMAC LINK OMRON network. If Node Status is 1 the node is active.

access point vs router