This involves rally marshal control clocks based on Nook Simple Touch e-readers. This model Nook was used for the e-Ink display, which works better outdoors, than standard tablet display.
The initial work was done by NASA Rally Sports and this project is improvements to that work. The improvements include a new Android rally clock app, the initial version of which was written by Michel Hoche-Mong.
When the Nook Rally Clocks were used in the woods, away from WiFi and network services, their clocks can drift. This was problem was addressed by adding a small GPS, reading the NMEA messages with time updates and resetting Android’s system time. The system board on the Nooks has lines for an unused UART. This can be connected to the GPS board and GPS messages read through an Android serial port device, the messages parsed and the system time set with the time parsed from those messages.