Modbus address with letter?

How would I write 40110.b I get a format error with .b?

Thank you in advance

b is supposed to be a digit, or pair of digits, that select a bit number from 0 to 15.

Also, if the 4 indicates a holding register, you would replace that with HR on the Ignition side. So, [someDevice]HR110.15 would yield a boolean for the high bit of that holding register.

I tired to map like this

But i can't connect to the device. I noticed it connected, but after i edited the mapping it just keeps disconnecting again. Any ideas? the .b should be a heartbeat. When it did connect a bad tag value.

Not in this reality.

Skip the address mapping. Review the address syntax in the user manual. Consult the documentation you have for this device to figure out what address the "heartbeat" actually represents.

No documentation for said device. Only info I have is whats already setup in the HMI program (advantech). I know device IP and registers, but thats it.

This address, taken literally, doesn't mean anything outside of the system that invented that syntax. You've gotta figure out what it means to translate it to Ignition.

Phil already probably guessed correctly that it's HR110 as the base, but the .b is not obvious to me.

any idea why I was only able to connect once to the device?

Often Modbus devices will close the connection if you read an invalid address, or don't read anything with in 10-15 seconds, or because you looked at them funny, or because the stars aren't aligned.

The Ignition Gateway logs probably have some errors or warnings in them.


Here is my log for warnings

Well, that's the device telling you the address you're requesting is no good.

Go back to the advice we both gave you earlier.

No address map. Manually addressed tags. Read the manual for the syntax. Address HR110, not HR40110.

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Yeah no manual, trying to do a bit of reverse engineering i guess.

Might try this configuration below. You need to add the device address.. This would get holding register 40028 bit 5 or 6 depending on your device being 0-15 or 1-16 bit based.


what would ModemNum and DevAdd be? vs the above [devicename]

I couldn’t get the modbus address configuration to work under the OPC UA, Device Connections section. So I mapped the device in the OPC Item Path… Mine are using parameters but yours would look like. [someDevice]1.HR110.15

Notice I had to add the 1 for the modbus device address if it's the first device.
This allows the Device, then modbus device address, then the holding register then the bit to read.