EC200U on evaluation board not receiving AT commands while sending at COM1(main) using RS232 adapter

Knowledge Base Serial
1

hello team,

After many struggles i have installed the driver for RS232 on my pc having windows 11 operating system so now it showing the USB to serial port with a COM18.After that on qpycom i have opened the port and i also connected the usb cable to my pc then i tried to send AT commands using this RS232 which is connected at COM1(main) of my evaluation board but nothing happened there and while trying with AT port and modem port, the AT commands are working perfectly then what happen to this RS232.Can anyone please help me out i was struggling here for nearly 3 days i was trying to send raw hex data using docklight but that process also unsuccessfull

2

Do you use the main UART or USB of the EC200U for AT communication?

3

i used both, it worked with usb i mean it returned OK while sending AT using usb but while using COM1(main), the AT command not even sending.

4

This issue is usually related to the hardware design of the UART. I suggest you carefully examine the circuit of the UART and refer to our HD reference design

5

So, what I need to do to get rid of this issue.Can you provide me that HD reference design of uart.

6

I have sent the manual of HD and the reference hardware design to your email

7

Thanks alot for your responce i got the point where the issue rises, that level shifters are not working anyhow im using jumpers to get the data so now i want to send AT commands to the ec200u through uart in python code and it should respond to that commands.So can you please send me any reference code to send AT commands to the ec200u.

8

I have sent the docs to your email, pls check