Revo chip replacement
« on: June 13, 2016, 01:43:31 pm »
Hello!

Recently i burned my revo mini (connected 12v to flexi port)
I ordered a new ARM and replaced it. Now all the fun starts. I downloaded the Flash loader demo and succesfully uploaded the revo bootloader to the chip via mainport with FTDI. But now the GCS does not see it. In device manager the ARM is seen as "STM device in DFU". The STL pads are not connected and the power was cycled many times.
I ran out of options...
Checked the pins everything look great....
This is a revolution mini.. Same as revo but without oplink transmitter

Re: Revo chip replacement
« Reply #1 on: June 13, 2016, 01:53:01 pm »
Just checked the oscillator... 175ns period sine wave... So that means 6MHZ.. The circuit diagram doesn't state the frequency but i assume it is correct. Since the ARM runs at 168MHz that means divider of 28... The frequency is PLL source. 
Did i mess up any fuse bits?
Thank you!

Re: Revo chip replacement
« Reply #2 on: June 13, 2016, 02:00:26 pm »
I forgot to tell the most important thing... No leds flashing or blinking.. Dead... But that i suspect is because the chip is in DFU mode... The bootloader pin is at 0v so no bad soldering or floating pins...

Mateusz

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Re: Revo chip replacement
« Reply #3 on: June 13, 2016, 02:16:25 pm »
Since you stated that chip enters DFU mode, then it means it is functioning correctly. I would check for shorts. You could check with multi-meter your SBL pads, if there is a short somewhere.
If it beeps, one could try reflowing chip pads with some more flux and a very tiny bit of solder. Just an idea. Chip in DFU is in a STM bootloader mode, meaning that SBL pads are connected and it's not booting the firmware, so GCS won't see it like that.

Re: Revo chip replacement
« Reply #4 on: June 13, 2016, 02:22:20 pm »
Just looked again at the 10k pulldown resistor... It was broken... Now i can get the device out of dfu mode (dissapears in device manager) but still nothing .... No leds, no new devices in device manager.. Gcs does not detect it.. So now its a firmware problem

f5soh

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Re: Revo chip replacement
« Reply #5 on: June 13, 2016, 02:36:58 pm »
If you flashed the bootloader now you need to flash the firmware or nothing happens while connected.

- Disconnect board
- Hit Upgrade&Erase button
- Connect board

Wait until the board rebooted and erased flash.

There is other way than FTDI for Revo board recovery:
- using usb only:
https://librepilot.atlassian.net/wiki/display/LPDOC/Recover+board+using+DFU

- using Stlink:
https://librepilot.atlassian.net/wiki/display/LPDOC/Recover+board+using+ST-Link





Mateusz

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Re: Revo chip replacement
« Reply #6 on: June 13, 2016, 02:45:53 pm »
You can try flashing ef image (ef = entire flash = bootloader and firmware) which is provided in bin file and can be uploaded while in DFU mode with dfu-util tool.
 

Re: Revo chip replacement
« Reply #7 on: June 13, 2016, 02:58:14 pm »
Can you point me to the bin file? Is it uploadable with the stm flash demo?

f5soh

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Re: Revo chip replacement
« Reply #8 on: June 13, 2016, 03:07:26 pm »

Re: Revo chip replacement
« Reply #9 on: June 13, 2016, 05:24:33 pm »
Thank you! I will try this method. Previously you sead flash the bootloader and connect to GCS and hit recover... That doesn't work

Re: Revo chip replacement
« Reply #10 on: June 13, 2016, 08:37:47 pm »
it worked... just to clarify things... first upload bootloader via RS232 an then flash with the utilities you provided? Or can it be done only via USB with you utilities?
The board connects, i had to manualy upload the latest firmware. But now i have problems with calibration. the board is not level even if i do all the calibration procedures. I had to manualy change the Board level trim so the boar now sits level. I think i had problems before i burned the main processor...
Is it normal that the main vhip gest quite warm? the data in GCS shows 40 degreen for sensors?

Thank you!

f5soh

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Re: Revo chip replacement
« Reply #11 on: June 13, 2016, 09:29:45 pm »
CPU temperatures around 40° looks normal (the one displayed into PFD panel)

Take a look about calibrations here:
https://librepilot.atlassian.net/wiki/display/LPDOC/Sensor+calibration


ef_revolution.bin can be flashed using DFU method or StLink dongle.

Re: Revo chip replacement
« Reply #12 on: June 14, 2016, 07:25:01 am »
Thank you!

The revo mini works great! :) now i have a spare one :)

Re: Revo chip replacement
« Reply #13 on: June 14, 2016, 10:57:19 pm »
hmm strange... i have been playing around today with calibration... Did every calibration with no luck... if i manually trim the board level in Data objects it work, but if I do the calibrations it's no good...
Now i installed Librepilot 15.09 an uploaded it's firmware all is good.
I only did the board level calibration and it perfect... seems to me that there are some bugs :)