Modbus TX sequence from Nucleo is missing some bytes

[LysAn]

Hi all,

 

the Modbus-serial bit sequence my Nucleo_H7A3ZI_Q is generating (as a client) looks good in the console terminal on my computer. However, at an oscilloscope, two of the bytes are missing: the function code 03 and the part of the CRC (cyclic redundancy check) section. Two images are attached. I build and flashed the program with Zephyr RTOS. Any help is appreciated.

Thanks