Writing data in to a holding register.

Question

Writing data in to a holding register.

MaxAbarca1993 opened this issue 5 years ago · 10 comments

MaxAbarca1993 commented 5 years ago

Hi Bertmelis, I'm so iterested on this library, it worked very well for me, but i don't now if it has implemented the write holding regiters yet. I really hope if you can help me with this. I'm working on a water well system that needs to send data via modbus tcp and store it on a database, so, the data acquirer is a ESP32 board. Thank you very much for your work, it was a great advace for my proyect.

Answer 1 · 2020-03-12T12:26:26.000Z

Hi MaxAbarca1993,
Did you get something? I have to do something similar as you.
I'm looking forward to hearing from you!

Answer 2 · 2020-04-22T09:30:17.000Z

Hi MaxAbarca1993,
Did you get something? I have to do something similar as you.
I'm looking forward to hearing from you!

Answer 3 · 2020-04-22T14:12:00.000Z

I'm writing a completely new version. The current TCP management has a few flaws. I'll upload the new version this evening (in a new branch). API stays the same. It'll include FC03, write holding registers. (I already have FC06, write single register)

Answer 4 · 2020-04-22T20:12:36.000Z

Please have a look at branch v1.

I was a bit confused earlier. Do you need FC06 (write holding register) or FC16 (set multiple registers).

Answer 5 · 2020-04-22T20:30:12.000Z

Hi bertmelis, first of all, thanks for your work and your answer. About your doubt, I needed FC06 write holding registers for my project.

Answer 6 · 2020-04-23T09:01:17.000Z

Ok, FC06 is included in the v1-branch. Could you try this? I'm not able to test in various situations because I don't have any modbus devices anymore.

Answer 7 · 2020-04-24T04:07:43.000Z

Hi bertmelis, I have already use your code to read and write data to holding register and it's works but I can't set my cycle time for read and write less than 1 second and status modbus always connecting.

Answer 8 · 2020-04-24T06:52:42.000Z

You mean you read and write every second? I'll try some stress testing myself, but that's pretty fast for modbus.

So it works but not if yo read/write too fast?

Answer 9 · 2020-04-24T07:30:50.000Z

I have project to controll and monitoring some modbus device, and I need to read and write registers about 50ms/looping to chasing realtime. Is it possible to use modbus protocol?

lastMilis = 0; if ((millis() - lastMillis > 50)) { lastMillis = millis(); MB.readHoldingRegisters(address, length) }

Here code for example what i want. Thank you very much

Answer 10 · 2020-04-24T19:55:44.000Z

Maybe it is possible but I wouldn't use modbus to poll a device every 50ms. May I ask what kind of project you're building?