Error Sending data to Arduino through UART Communication

[Malre.1]

Hi,

I would like to send a data from my STM32F401CC to Arduino.

I have connected Tx to Rx and successfully upload the code to stm32 and Arduino Uno.

I don't get the values right, only first four readings, then all the values become random.

This is my stm32 code:

 

and this is the results:

 

the Arduino Uno code:

 

I configured both clocks to be the same 16Mhz.

Please, Any IDEAs?

[Tesla DeLorean]

Issue at Arduino end?

Try looking at STM32 output with scope or USB to CMOS Serial dongle.

Try increasing delay from 1ms to 250 or 1000.

Software Serial?​

[Malre.1]

Yes.

If I connect the UART to usb serial port through (FTDI converter) I would get a perfect results in the serial monitor.

Which means, If I connect the stm32 directly to the serial port it is working, but If I send a data to the Arduino then display it from the Arduino end using its serial port, it doesn't work.

( I just want to implement the UART to UART protocol)

tried to increase the delay, same problem.

[LCice.2]

Hello malre.1,

hello everyone,

in the Arduino code,

in the callback function : "Serial Event ()" why did you put a "potentially infinite loop" ?

if "SerialEvent () is really a callback function, in my opinion you should process 1, 5 or ten bytes, and then let the function exit.

Instead, doing your way, the SerialEvent() could potentially never return if the serial port is flooded with bytes.

(But... I do don know anything about the Arduino platform :).

Please, try to process at most 4 bytes, or at most 10 bytes, and let us know...