Bootloader in UART mode not responding correctly and also not working with Cube programmer.

[VTaya.1]

Hello Community.

I am using STM controller STM32L432KC with

Baud rate I have tried from 1200 to 115200.

1 - stop bit

9 bit data ( including parity ) as this is the only configure option available in STM32CubeIDE. 

Even Parity enable.

1 - stop bit.

 as host controller to access flash memory ofSTM32H723ZG controller.

I have application code running in STM32H732ZG controller which toggles the LED and put the received byte on UART3 PD9_RX pin over UART3 TX pin PD8, this is to verify that UART RX TX connection are properly connected.

Now, by holding Boot0 pin HIGH as per pattern_10 for STM32H7xxx series from boot loader document. I am providing reset condition to STM32H723ZG controller and controller starts to execute bootloader. (This is confirmed because SPI boot commands are working , SPI connections are removed after testing ) 

Do I need to connect RTS and CTS while communicating in UART Boot mode ? 

On sending 0x7F byte with some delay over UART3 after reset , I am receiving some response from STM32H723ZG controller , but its not at same speed as synchronize byte , its something garbage pulses as can be seen on logic analyzer, ill share the screenshot soon. 

More over on connecting STM32H723Zg with cube programmer , there also its not working in UART mode. 

Is the issue in cube programmer UART mode ? 

Thank you .

Vaibhav.

[Houda GHABRI]

Hi @Community member​ ,

Sorry for the delay.

Can you please specify the STM32CubeProgrammer version used?

if it is not 2.7.0 can you please switch to it as it contains an update on H7 UART connection?

Houda

[VTaya.1]

Hello @Houda GHABRI​ 

Thank you for responding.

I have switched to SPI protocol for firmware update in boot mode and upgraded controller from STM32H723 to STM32H745II.

I am able to communicate with STM32H723 (single core ) controller in SPI boot mode over SPI3_port on PC10, PC11, PC12 and PA15 pins , but facing issue with STM32H745II (dual core controller) interfacing over same connection. ( connections are valid according to boot mode application note provided by STM )

Is it possible to get support for STM32H745II dual core controller SPI boot mode ?

My host controller configurations are following.

• 3.3v operating voltage.
• SPI speed 3Mbps to 8Mbps.
• SPI data frame at 8 bit MSB first mode.

Host controller working fine with STM32H723 controller, host is able to sync in SPI boot mode and perform operations in SPI boot mode. ( memory erase, memory write, execute GO command, etc )

Same host with no change in code, interfaced to STM32H745II controller wont work.

Can you please proved any example for communicating with STM32H745II dual core controller in SPI boot mode.

Thank you.

regards @Community member​