Tiny standalone single sketch Arduino APRS tracker based on modified version of LibAPRS with external GPS module

Arudino APRS tracker is based on Arduino UNO with next periherals:

• Nokia screen, PCD8544 - https://www.sparkfun.com/datasheets/LCD/Monochrome/Nokia5110.pdf
• Rotary encoder - https://www.sparkfun.com/products/15140
• Micromodem from marqvist - http://unsigned.io/micromodem/
• GPS receiver, SkyLabs SKM53 - http://www.skylabmodule.com/gpsmodule-antenna-skm53/

• Minimum: Arduino UNO with 2k SRAM, 32k FLASH
  • may require some manual libraries optimization, such as buffer size decrease
  • or different screen, PCD8544 requires 500 bytes of RAM for the buffer
• Recommended: Arduino MEGA with 8k SRAM
  • NB! needs some tweaks in LibAPRS internals

• Simple timer - https://github.com/jfturcot/SimpleTimer
• Rotary (rotary_button branch) - https://github.com/sh123/Rotary/tree/rotary_button
• Modifed LibAPRS (aprs_tracker branch, check device.h for ports and pins usage) - https://github.com/sh123/LibAPRS/tree/aprs_tracker
• Tiny GPS - https://github.com/mikalhart/TinyGPS
• Adafruit PCD8544 - https://github.com/adafruit/Adafruit-PCD8544-Nokia-5110-LCD-library
• Adafruit GFX - https://github.com/adafruit/Adafruit-GFX-Library

• Rotary encoder rotation iterates over transmit heuristics selection, such as periodic transmit every 1 minute, 2 minutes, 500 meters, etc.
• Short encoder release activates current heuristic if it is different from the current one or iterates over different APRS SSIDs
• Long encoder release forces current position to be sent out