SensorTile.box does not power up after FOTA firmware upload
I have a big issue with the STEVAL MKSBOX1V1. I was making some attempts to work with the Vibration Monitoring Example (made up of "Training" and "Compare" sub-processes). After having successfully run the example on the firmware preloaded on the SensorTile.box, I made some changes to the examples in order to stream data over Bluetooth, so I uploaded a custom firmware. Af this the SensorTile proposed to me to upgrade to firmware 3.4.9, so I accepted it and the new firmware was correctly uploaded. I noticed however that the example didn't work correctly anymore, since the "switch lamp" that should be light-on only when an anomaly vibration was detected, was always lighted on after the firmware upgrade.
So I checked the possibility to swap to previous firmware version, but no possibility was provided within the app and on the ST site, associated to the STEVAL MKSBOX1V1, I found only one firmware with description "SensorTile.box firmware OTA function restore". In the details "The STSW-MKSBOX1_BL firmware allows you to restore the ability to upgrade firmware over the air (FOTA) in the event that FOTA functionality is overwritten or deleted due to a custom firmware upload.", so I believed that, uploading this firmware, I could be again able to upgrade the firmware via FOTA to the most desired firmware version. Downloaded the file on the smartphone, I uploaded it to the SensorTile via the ST BLE Sensor app.
After correctly uploading it, the app said the board would restart after disconnecting and from that moment the board is dead (it is no more recognized from the pc when connected to USB neither any led blinks on the STEVAL).
I read later in this post ((https://community.st.com/t5/mems-sensors/sensortile-box-steval-mksbox1v1-doesn-t-turn-on-and-some-more/td-p/82904) that:
* the vibration example does not run correctly on the last firmware version, but runs in previous versions (<=3.4.7)
* the same boot problem was already occurred in the past to another user. I have already tried the procedures suggested in that post (and in the linked one), but, even after disconnecting the battery, pressing the power button, connecting the USB cable and releasing the POWER button, the STEVAL remains off and cannot be detected by the STM32Programmer. The board cannot be used anymore.
The cable I am using was able, before the problem, to correctly transfer data between pc and SensorTile and show the STEVAL memory card content as a removable partition on the pc.
So my question is: how is it possible the firmware upload has harmed the SensorTile.box? And: how it is possible to recover it? I am just wondering why on the ST site there is a link to a firmware that potentially can harm the SensorTile and no link to version 3.4.7, 3.4.6 and previous firmware versions...
Thanks in advance to experts who can help me with this big issue.
