See also https://github.com/ohanssen/ArcticTracker-ESP32
Arctic Tracker is an APRS tracker platform based on the Teensy 3.2 MCU module, a SR_FRS_1W VHF transceiver module and a ESP8266 WIFI module (ESP-12) with NodeMCU. The ESP module will function as a WIFI interface, a webserver and possibly a storage for data files. A small display and a PA module will also be condidered.
See http://www.hamlabs.no for more info about this project.
This is the firmware for Teensy 3.2 MCU. It uses ChibiOS/RT RTOS. It is partly based on the Polaric Tracker firmware source code. Implemented features include sending/receiving of APRS packets and communication with the WIFI module. Code for the WIFI module is implemented in LUA/NodeMCU and can be found in a separate GIT repository.
Build requirements:
You will also need a tool to install firmware on a Teensy.