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sparkfun / SparkFun_RTK_Firmware

Centimeter precision GPS/GNSS using L1/L2 signals broadcast over Bluetooth SPP (using the ESP32) in an easy to use enclosure.
https://docs.sparkfun.com/SparkFun_RTK_Firmware/
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Device incorrect identifies as RTK Surveyor #737

Closed nseidle closed 9 months ago

nseidle commented 9 months ago

v3.8 was the first version to use the tighter tolerance value of 4.75%. Prior to that version, the tolerance windows were very large (10%).

Some ESP32 have an incorrectly trimmed ADC fuse. This leads to the ADC reading of the device ID resistors being slightly wrong. This leads to some devices being improperly ID'd. When the device can't ID itself, it defaults to the Surveyor type.

It seems very rare. We've only seen a few devices (5 currently) that exhibit this behavior. The solution is to increase the ID windows by increasing the tolerance as well as calculating the upper and lower thresholds more accurately.

nseidle commented 9 months ago

I believe this is what @Stefal was experiencing in #735 but I'm not complete sure.

nseidle commented 9 months ago

Fixed in v4.0.