"STM32 microcontroller system memory boot mode" with bluetooth module

[HamedTahamtan]

hi every one . 

I want to program my stm32U5 microcontroller with a Bluetooth module that connected to Uart 1. 

I decided to Use "STM32 microcontroller system memory boot mode"

also I use stm32cube programmer software for programing the MCU. 

at first I tried to program the microcontroller by connecting the uart1  RX/TX directly with a usb converter to the pc. and it was successful. below you can see the programing process . 

for the next step I connected the bluetooth Module to my microcontroller and try to do it again but I faced a problem .

so I decided to monitor the serial port to see what happened . 

in the normal situation the serial monitor is like this 

but when I use the bluetooth module it will be so:

so I realised that the problem starts from the second command(02 fd).

I tried to send the commands with a serial port to the MCU but when I send the command "02  fd" it will return 1f to me and that is wrong. 

as I know from the aplication note an3155 that this line contins two different commands , I have done it in another way so that: at first I send the command "02" and with a small delay send "fd" then it works well . you can see also the results below 

now I want to know where is this problem comes from . and how can I solve it . 

or is there any other software or way or configurations  that you can suggest me to program my microcontroller with ?

[SofLit · Accepted solution]

Hello,

Better to probe the Tx and Rx and see the bahavior. It could be somthing related to your Bluetooth module.