Support for Xiaomi Mi 3C

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