How to flash firmware image through uart in stm32l476-discovery

[samuel_zhang]

Posted on November 03, 2015 at 03:14

Dear all:

I wonder how can I flash firmware image from PC through uart port (uart1/2/3) in stm32l476-discovery board.

It is said in reference manual ''nBoot1'' should be set to 1 which represents so called ''Boot0'' - a virtual port would be set to low level. Then one can burn image through any uart to internal flash.

But I don't know how to set the register ''nBoot1'' to 1 in condition of no way to write register after reset.

I also tried to ignore this setting and just set ''Boot0'' to VDD. But each time, for each UART, same error occurred: ''No response from the target...''.

So I'm here to look for your help on this issue.

Anyone who has STM32L476-Discovery or NUCLEAR board on hand, please give me your hand.

Thanks. 

#stm32l4-discovery-uart-bootloade #stm32l476-discovery-uart

[Tesla DeLorean]

Posted on November 03, 2015 at 03:40

I'm not sure the on-board VCP is the ideal medium to do this, or whether the older Flash Loader Demonstrator supports the L476 models.

I'm pretty sure the setting of nBOOT1 will be fine by default, so setting BOOT0 High and resetting should be sufficient to get into the System Loader.

I'd suggest you use a terminal app like RealTerm, configure it to connect at 115200 8E1 (Even Parity required), and send a hex byte of 0x7F to the part. You should look for a hex response of 0x7F

[samuel_zhang]

Posted on November 03, 2015 at 08:32

Thanks very much.

I have approached what you said - echo back ''0x7f'' in this board through usart3(PD9/10) - onboard SEG18/5 pins.

But the software ''flash loader demonstrator'' can't recognize STM32L476 core as below - seems not supported currently.

 It told me ''Unrecognized device...'' if I set baud rate to ''115200''.

Please ST engineer advice how to fix the bug.

[Tesla DeLorean]

Posted on November 03, 2015 at 14:35

That should have read ''0x79 response''.

This is a user forum, I'll push this to moderation. You could also contact via local ST sales/support staff of distribution channels, and associated FAEs