# Possible bug when calibrating ESCs on ModalAI's custom 1.14 flight core v2 firmware

Source: https://forum.modalai.com/topic/2871/possible-bug-when-calibrating-escs-on-modalai-s-custom-1-14-flight-core-v2-firmware
Category: Flight Core and Legacy VOXL (https://forum.modalai.com/category/9/flight-core-and-legacy-voxl)
Tags: flight-core-v2
Posted: 2023-11-16 19:47:39 UTC by John Nomikos 0
Replies: 0 · Views: 639

## John Nomikos 0 · 2023-11-16 19:47:39 UTC

Good afternoon,

Today I was attempting to calibrate my ESCs when I ran into a strange issue. I press the "Calibrate" button to calibrate the PWM escs, but nothing happens. I tried this on multiple versions of QGC. 

I am using the custom 1.14 firmware available here: http://voxl-packages.modalai.com/dists/fc-v2/sdk-1.1/

As a note, this FCV2 serves as an external flight controller for the VOXL2, and the ESCs are plugged into the flight core.

Also, I was following the regular instructions for calibrating ESCs. I plugged into the FCV2 via USB.

Interestingly enough, I flashed the stable release 1.14 firmware and did not see the same issue. I was able to calibrate the ESCs with no issues on the stable 1.14 firmware.

--

Another (slightly) related question. What is the difference between the custom Flight Core V2 firmware that ModalAI provides and the stable release? I am curious if it is a bad idea for me to use the 1.14 stable release.