AnsweredAssumed Answered

How to revive a dead MCU in-circuit?

Question asked by Williamson.Mark.002 on Dec 18, 2016
Latest reply on Mar 17, 2017 by avi_crak.videocrak

Hello all!  How's this for my very first question


I purchased a 3d Printer on clearance with a tag that says Does not Start up.  No warranty.  I was ok with that.  As I'm a developer and a hardware hacker I knew I was buying a project not a printer.  I have experience with Atmel, wrote my own firmware for a Cricut cutting machine, so I'm comfortable here.


The situation I believe is that the store had upgraded the firmware on this machine but used the wrong firmware.  There is much discussion about this situation on the internet from this particular brand of printers. Overall, the quality of the printer is great.  So now the problem.


The images show that the MCU is an STM32F407ZTG6.  I can see clearly that it has SWD header yay.  So I connected the STLink board from my Nucleo to it, removing the jumpers so that I can use it to program an external device, connected the 3.3v power pad on the 3D Printer's board to the 3v3 header on the Nucleo, and I can tell the board has power.  However, STLink does not see the target.  Anyone have some ideas to help revive this guy?