Hello,
I'm using a esp32 connect directly to other Uc (TI) and the communication between both of them is by Modbus RTU (not using rs485, only serial ports).
I can't receive the response messeage from Function 04 or write a coil from Function 05.
If anything have an idea or an example it will be welcome.
Thanks a lot.
Modbus Master Serial RTU without RS485
Modbus Master Serial RTU without RS485
Hi! I'm a PCB designer and a Uc programmer from Argentinia.
Re: Modbus Master Serial RTU without RS485
Use something like Baseblock ComTest Pro to sample the messages on a PC http://www.baseblock.com/
You will need to connect with FTD module od similar
You will need to connect with FTD module od similar
Re: Modbus Master Serial RTU without RS485
rodmcm wrote: ↑Mon Sep 28, 2020 1:05 amUse something like Baseblock ComTest Pro to sample the messages on a PC http://www.baseblock.com/
You will need to connect with FTD module od similar
Thanks u so much! I ve tried a lot of thingg and I forgot watch the signal by osciloscope. When I tried that, I have no response from the TI microcontroller because my partner forgot enable Serial communication...
I will refresh this post when I have a good result. The modbus communication is very important and there is no much related information for this enviroment.
Anyone can ask me why I choise Arduino IDE enviroment for the professional job.. and the answer is... Because if You can program C or assembly, arduino has no more problems than other enviroment.
Hi! I'm a PCB designer and a Uc programmer from Argentinia.
Re: Modbus Master Serial RTU without RS485
Hi again. The next (and I hope the last) problem is:
How can I generate a silent interval between two frames. More detailed, an interval equal to character *3,5 or more.
If anyone know the answer, please post here! Thanks!!
How can I generate a silent interval between two frames. More detailed, an interval equal to character *3,5 or more.
If anyone know the answer, please post here! Thanks!!
Hi! I'm a PCB designer and a Uc programmer from Argentinia.
Re: Modbus Master Serial RTU without RS485
send null characters
Re: Modbus Master Serial RTU without RS485
Thanks! I fixed it yesterday.
If the library is required I can made it else I can receive questions about the format.
Good bye!
Hi! I'm a PCB designer and a Uc programmer from Argentinia.
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