STM32H745i-DISCO bricked no connection even with boot1

[CChri.5]

Hi, I have recently bricked my STM32H745i-disco board by turning off the m4 core within OB which had a bulk of my code. My board became unresponsive, the LCD turns white and the leds on the board light up but do not respond to the reset button. Stlink says cannot connect to target, but I can update firmware.

I have moved over the resistor across to set boot0 to boot1, however stlink programmer still does not see the board so that I can do full chip erase. Moving the resistor has shown no difference.

any help going forward would be greatly appreciated

cheers

[TDK]

Connect to the M7 core on AP0 instead of the M4 core on AP3.

> Stlink says cannot connect to target, but I can update firmware.

How are you updating firmware if ST-Link can't connect?

Does STM32CubeProgrammer detect a voltage? What is the exact error message you're getting? Screenshot is the most helpful.

[Tesla DeLorean]

The BOOT0 = HIGH solves a different issue, not messing up the Option Bytes

Typically it deals with power supply issues of LDO vs SMPS, and requires completely power cycling the board.

One might look at the connect under reset options, or the connectivity setting in general.

Did you do the OB settings from your code? Show code

[CChri.5]

Thanks for you r resposnses. Attached are screenshots from the STM32CubeProgrammer. I set the OB settings through the programmer, but as I cannot connect I cannot turn the M4 core back on. As you can see the programmer cannnot connect. But I do have th eoption to Upgrade Firmware.

[Tesla DeLorean]

The firmware on the chip with the ST-LINK/V3 (F723) functionality, not the STM32H745I.

Not the same CPU

Not sure how you're going to unbrick that.

Can you connect to the H745's USB, with BOOT0=HIGH, jumper set to power via USB ?

If the H7 is viable you might get a "STM32 BOOT DEVICE" type enumeration.

[CChri.5]

I have moved the usb into "POWER"port, moved the jumper over to USBPWR. STM32CubeProgramme says Error: No debug probe detected.

[CChri.5]

Reading an older thread, it has made it apparent I might have accually turned off the 7 core. Not good.

[CChri.5]

Turns out thats exactly what has happened, in ST Utility, CM7 was unchecked. Thats solves what the issue was. Now to try and fix it

[CChri.5]

Successfully connecting!^^

[CChri.5]

Internal parameter error. Can't seem to do the final erase! So close!