bricked stlink on my stm32f746G-dicso devkit

[karushifa]

Hi

I had the stm32f746G-disco development board laying around, after while I wanted to try some application, during flash I got warning that my st-link firmware was old, I wanted to upgrade it but failed during upgrade, anyway it was very old firmware. Well I had another st-link at hand, I have connected it to the SWD port on the dev-kit, *** me I thought it is connected to stm32f7 but after pressing erase flash I saw the connected MCU is stmf103, well I accidentally erased the st-link, long story short it was a *** mistake.

I have been searching online there are lots of suggestion, I am very confused, is there a way to recover the on board stlink. Because there is no jumper or pin that exposes SWD/JTAG pins of stm32f7, I need to recover it.

I have tried "java -jar STLinkUpgrade.jar -d8_d32_msc_br -force_prog" with stm32f407 nucleo board but no chance.

Any help appreciated thanks.

[mƎALLEm]

Hello,

Did you connect over CN8 connector?

That was a mistake indeed. 

I don't think the STLINK is recoverable.

What I can propose is to use the solder bridges on the board:

Remove SB14 to SB17 to disconnect the STM32F7 from STM32F103 and solder wires using pads from unsoldered SBs to connect through an external STLINK.

Hope that helps.

[AScha.3]

Hi,

only chance to get the onboard st-link working again, is to flash a bootloader...then update to st-link.

You could try...otherwise just use another st-link, as  mƎALLEm wrote . Onboard is no st-link now.

[karushifa]

Thanks for answers,

Sorry to hear that it is not recoverabled. But as suggested, I ll do what mƎALLEm wrote. 

But still @AScha.3 which bootloader actually are we talking about? I would to give it a try.

[MM..1]

Simple tip buy cheap nucleo and swap 103. 

[karushifa]

Good idea to save the disco :thumbs_up: but for now I have soldered jumpers to CN8 and removed solder bridges; SB15 and SB16 and connect them to CN8 to be able to use external ST-Link