help programing bootloader devo 7e, it don't work

Hi Guys

My Devo 7e burned in yesterday because i wrong power lipo and it short circuit .
I bought a chip Stm32f103rbt6 same stock devo 7e and a Stlink usb . i looking for on forum and i see file Bootloader devo 7e ( not devo 256k ). After load bootloader , the transmitter is still failed to power up, there is no crystal oscillation signal at the 8MHz crystal.
Anyone know this please help me .
thanks

you will most likely have burned out the voltage regulator i would have thought

HappyHarry wrote: you will most likely have burned out the voltage regulator i would have thought

i replaced it (voltage regulator ( and Mcu . I measure power MCU 3,3v now .

thisis photo after i loaded bootloader

sorry you didn't mention it in the first post, this happened to me recently when i attempted an upgrade of the mcu in my 7e, the bootloader wrote to the chip fine but the tx would never power up, unfortunately i didn't have the skills to debug what was wrong so i can't help you any farther.

you may want to edit your post title as many will think you are asking for help setting up models, you should add 'bootloader' to the title

thanks , i edited title .

i hope someone help .

If don't have a EPPROM 25F16 or LCD , it can work ? I afraid i miss pins from Mcu when solder

martin88 wrote: there is no crystal oscillation signal at the 8MHz crystal

That would be a problem. You can program without the crystal (I think it uses the internal oscillator during programming), but things won't run without it I think. Someone else might confirm this cause I've never tried personally.

martin88 wrote: i replaced it (voltage regulator ( and Mcu . I measure power MCU 3,3v now .

Are you measuring the power with the switch in the on position or with the power bypass pins shorted to each other. Make sure you have power using the power switch, if not look at the few fets near the power bypass pins, they could have been damaged. A few people here have already had those let out magic smoke. You would have still been able to program if those fets are dead cause the programmer would provide power. You can also try to short the power bypass pins, I believe (not sure but I think so) these don't go through the fets so you may see the tx come to life.

martin88 wrote: If don't have a EPPROM 25F16 or LCD , it can work ? I afraid i miss pins from Mcu when solder

With no flash things will boot up, but you will be stuck in USB mode to format the drive. No LCD then you see nothing, so definitely check your solder joints.

Goodluck! Let us know how it goes.

in real , when i connect Pin boot0 to 1 or do not connect , i still can load program ok , and then i remove jum boot0 .

even , i use power from usb stlink , it not change .
have crystal , but i use Osc to test signal , but not see Frequency .

i try load a other firmware for chip , it work with this program .But when i come back to load Bootloader , it don't work .

hard for me Hu hu hu

That sounds like the problem HappyHarry had which we still haven't found a solution for.

If you have access to a usb-to-ttl device like a ftdi board, could you try to see if you can connect to the onboard bootloader via uart without boot0 connected to vcc? You'll need to use stm flash demonstrator for this. The pins are on the 4 pin dsc port on the right side of the main board. Counting from bottom up, pin 1 is tx, pin 3 is rx and pin 4 is ground. You'll need all 3. Also measure the voltage at the boot0 pin. Hopefully nothing is pulling it high and getting you stuck in the system bootloader.

[edit] One other thing is possibly to try pulling boot0 to ground through a resistor (maybe 4k7 or 10k?).[/edit]

although the third chip I (rdt6) tried turned out to have continuity errors the first two chips (rct6) i tried certainly didn't, I know for sure as I checked every last pin more than once, I'm now at the point of thinking the first batch of chips I had were faulty, what with the issue of how their properties didn't show properly in st's software and neither of the 2 I tried working, add that to the fact I've successfully done 4 more ult7e mods since the failure shows my methodology was good. so if you check for good continuity and find everything ok try ordering a new mcu from a reliable source and replacing it