If your device lost power during the upgrade, the SD file structure was damaged, or the firmware doesn't boot up for any other reason, you can perform one of the two emergency flashing procedures as follows:
First method:
- just simply press the hidden reset button on the back panel of the instrument and it will automatically flash with a randomly picked firmware .ptf file from the SD card Firmware/ folder.
Second method:
- download the Polyend Tool,
- download a known working firmware file either from the polyend.com/downloads or one of the previous .ptf files,
- important: remove the SD card from the Tracker,
- connect your Tracker directly to your computer with a USB cable (avoid USB hubs and dongles),
- power up the Tracker,
- in the Polyend Tool, choose the .ptf file you want to flash with,
- use a pin to press the hidden Reset button next to the Tracker's USB C port,
- wait for the firmware update to complete,
- if it's at 100% but the device didn't reboot on its own, do it manually,
- re-insert the SD card to the Tracker's slot,