On Windows: chip are sometimes detected, but writing often fails. With linux I have much more stability (chip detected and writed; not in 100% of cases, but often). Note: under linux, one of mine SPI programmers aren't detected (not listed with lsusb command), but if used under Windows are correctly detected (but programming fails)
No matter: in the end, I managed to program the bootloader. I also succeded recovery factory partition from an old backup. Now I have 2 router that are working. The strange things is that they mount identical content, but on one of them the cpu overheat. So that, after 10 - 15 min, router stop to works: one router with warm CPU, the other with very hot cpu.
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A little up-to-date:
On Windows: chip are sometimes detected, but writing often fails. With linux I have much more stability (chip detected and writed; not in 100% of cases, but often)...
Seems that is a simply power supply issue: I checked the Vcc, on chip flash, during programming: from 3.3 V it drop to 2.0 V and, sometime, to 1.0 V. Measuring current while flash chip programming, I detected 800 mA on a R3A board, 400 mA on damaged R3C and 100 mA on working R3C board. So I decided to use an external power supply, and identification & writing & readind are more stable. Maybe depend from how many current can supply the USB port where programmer is connected (and from programmer himself).
The issue that the programmer with 3V3 modify works only on one of my PC maybe depends from D+/D- voltage levels (also if, if I right remember USB standard, 3.3 V should be enought... but this is only my opinion, not tested).
The strange things is that they mount identical content, but on one of them the cpu overheat. So that, after 10 - 15 min, router stop to works: one router with warm CPU, the other with very hot cpu.
35 °C / 95 °F on working R3C board, versus 75 °C / 167 °F on "anomalous" R3C board. I decided to swap flash chip between boards and the behavior is identical. So I guess that, in the past, a bad programming of bootloader on one of the boards damaged her
Hello @eduardo010174 and @minax007
I currently have a working Mi 3C with Padavan (the MI-NANO one from this release) and my current bootloader is breed-mt7628-hiwifi-hc5661a.
Before making any changes to any partition, I had copied all the partitions (/dev/mtd*) and the partition table (/proc/mtd) to my PC from stock firmware 2.8.51_INT (Global version, not chinese).
What will be the proper way to switch to OpenWrt if:
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I want to continue using Breed as my bootloader? (Please also suggest another version of breed if there are any problems with the current version that I have)
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I want to switch to stock bootloader
If possible, please suggest solutions involving overwriting partitions (using dd) from Padavan shell as I am not very comfortable doing it from breed interface.
Thank you.
The Breed version is fine for this device.
But there is a better one when using Padavan. It is called "breed-mt7688-reset38.bin".
In that one you can reset the device correctly.
With regards to OpenWrt it is not possible to use Breed as it occupies areas of the memory which are used by OpenWrt.
@eduardo010174 had described earlier how to flash OpenWrt correctly. Just scroll upwards and you will find the instruction.
If you want to switch to stock bootloader then you need to flash the stock bootloader.
Some postings before I have shared the stock bootloader file.
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Hi,
I've also bricked my 3C by trying to move from the breed bootloader back to the original one.
Now I'm waiting till the clamp will be delivered to flash the SPI chip with a raspberry pi.
Unfortunately this link doesn't work any more. Which dump file should I use and is there a chance to edit the dump with a hex editor to put the mac address from my router in?
Hi,
sorry for my late response. I haven't been in this forum for quite some time and just saw your request.
Don't worry about having bricked the device.
By the clamp you have ordered it should be possible to fix it.
You need to get a dump file.
I see that the link does not work anymore.
There is a russian forum called "4pda", where you can find a dump for this router.
Just search for "4pda & mi 3c".
I wrote a blog about how to back to stock firmware. I use a full dump to first restore the sock bootloader then using the stock bootloader I successfully flashed the stock firmware. Here is the full instructions - https://biplobsd.me/blogs/view/restore-stock-bootloader-xiaomi-mi-wifi-router-3c-breed-web-recovery.md
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Many thanks to you for still replying. 
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Hi @NusaibTamim
the official OpenWrt can't be installed via Breed-Bootloader.
Please read the instructions above on how to install the official one.
If you want to try OpenWrt with Breed-Bootloader you can use the unofficial builds in my repository:
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Thank you very much
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Please download it e. g. from 4pda.
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