Dear Hopling ,

I checked the CRC calculation of the block and it is giving me "81 09" which is correct.

Now we will need to find out why it sends wrong CRC "01 09".

I dont have TIA can you print your program in PDF and upload or send it to my email?

Thanks.

I will try. Just upload it andwe will see.

Dear Hopling ,

I cannot open you project correctly in my version.

Kindly check the following parameters in theprotocol section of your CP.

Transmission Rate: sameas atslave

Data Bits: 8

Stop Bits: 1

Parity: same as at slave

I see data bits 7 in your configuration.

Change, tryand update me.

Good luck!

Alhamdulillah Hopling ,

I am very happy that it works now for you.

It would be interesting to know if it is going to work after migrationto TIA as well.

Actually theseparametersare a very good point to mention in the manual for other users.

Thanks.

I just migrated it to TIA without any problems...

It's working as good as it worked while using STEP7 V5.5!

Dear Bryll,

Bryll

This is something very useful you have done, thanks for sharing it

Useful for users is not always useful for vendors.

I hopeone day Siemenswill provide us with a freesolution like for the new PLC's.

Bryll

I haven't tried it yet, but will for sure next time I need a modbus master.

Yes pleaseand provide us with your feedback!

Bryll

Any plans of making a similar thing for a modbus slave ?

I have noplan forit at the moment.

Im currently working on transferring myModbus-TCP Client(code from 2003) from STL to SCL.

When I am done and have tested it I will share it as well.

Bryll

To any Moderator:
Isn't it a good idea to make this thread "sticky" below smiffys modbus information ?

Good idea? That dependsfor whom.

Best Regards.

TIBI68

Bryll

Any plans of making a similar thing for a modbus slave ?

I have noplan forit at the moment.

It's sad. It would be very usefull to have modbus rtu slave driver for using it with SCADA systems...

I was searching a solution for both modbus rtu master and slave drivers and I'm very satisfied now with your master driver! It's really easy-to-use and user-friendly! I'm using it now in my current task.

Could you make me some piece of advice about some other user written slave driver, maybe?

Dear Hopling,

Hopling

It's sad. It would be very usefull to have modbus rtu slave driver for using it with SCADA systems...

I never needed a modbus rtu slave in my projects only masters. That's the reason there is no slave driver existing from me.

Hopling

I was searching a solution for both modbus rtu master and slave drivers and I'm very satisfied now with your master driver! It's really easy-to-use and user-friendly! I'm using it now in my current task.

Your "positive feedback" is my reward, thanks.

Hopling

Could you make me some piece of advice about some other user written slave driver, maybe?

I am sure that there issome very good user written code out there but these usersare not willing to share their "hard work" with us.

Best Regards.

Dear Hopling,

the driver does not support reading/writingon trigger!

If there would be atriggerthe user would need to control the sequence by himself.

I took this headache from the userby executing all requestssequentially and headache free.

There is an advantage of cyclic transmission. In case of a transmission failure the values are written in the next cycle. This is not thecase when you write on trigger unless you handle it by yourself.

I know, you lose a bit performance.

What is your CPU cycle time with all 4 requests?

Best Regards.

Dear Hopling ,

this is just an idea and not tested but you can give it a try.

At the write request blocks you use a free flag bit (trigger bit) on EN input and reset it withDONE or ERRORoutputs fromthat request block.

I think you got what I mean

From the var table you can set the trigger bit to check it out.

Let me know your results.

Best Regards.

I forgot to mention that you will nee individual DONE and ERROR bits as well.

Dear Hopling,

I was very exitedso I check it out myself

It works great for me as well!

Thanks for your support!

Best Regards.