MSREGWR Run Every Scan

[RBPLC]

What's the feasibility of adding the option to allow MSREGWR to run every scan instead of edge triggered only?

[franji1]

What's the feasibility of adding the option to allow MSREGWR to run every scan instead of edge triggered only?

MRX/MWX already has all the flexibility you "need".  But the whole purpose of the Modbus I/O Scanner was to take care of doing all of that "polling" from a single configuration (vs. a bunch of MRX/MWX logic), then doing exceptions using MSREGRD/MSREGWR.

If you truly need it to be polled every scan, make it part of the Modbus I/O Scanner.  That's what it's for.

[RBPLC]

Let me pose a use case and you guys tell me a better way to deal with the issue.

I can see the Modbus Scanner being extremely useful. One issue I'm seeing is in attempting to use the scanner with a slave device that sometimes you would like to be able to locally control in a non-slave mode. If the writes are set up in the scanner, any local edits made to the device are immediately overwritten by the scanner utility. I agree, using the MSREGWR or the MWX is not ideal (as the scanner is meant to "just handle") the comms. What I'm looking for is a way to start and/or stop and/or one-shot the write portion when desired. 

[franji1]

Look at the specific Modbus Scanner Structure Heap Item and look at the .EnableWrites bit.

I think that's what you want.

[RBPLC]

.EnableWrites is what I was looking for. Obviously I forgot to check the scanner heap.

[franji1]

Attached is a screen shot of all the fields in a Modbus Scanner Device.  They also show up in the Modbus Scanner Monitor tool (under the Debug menu).  The Help topic DMD0493 Modbus I/O Scanner Configuration talks about those fields.

[Controls Guy]

I like that the status display is editable -- enabling and disabling reads and writes, shortcut to edit the device, etc.   Useful for debugging the comms.