TruePosition GPSDO monitor

Simple monitor device for trueposition gpsdo.

Tested only with version 12.1.1 of firmware/bootloader.

What does it do?

It boots up GPSDO by sending PROCEED command to bootloader. And it monitors status of antenna, 10mhz and 1hz signal, and actual device state.

LCD display shows current GPS time and date converted to UTC, temperature, and state.

If abnormal state is detected symbol is displayed next to current date.

• ~ = 10MHz signal trouble
• p = 1Hz signal trouble
• Y = antenna trouble.

After pressing button (long > 8sec), survey mode is entered. LCD displays survey time left.

What do I need?

• bluepill stm32 board
• 2line LCD display with I2C connection
• button
• STM32 programmer or 3v ttl serial cable - to program the mcu.

Pinout

• PA8 - PPSin - pin 11 on gps

• PA9 - UARTtx - pin 3 on gps

• PA10 - UARTrx - pin 7 on gps

• PA12 - button 1

• PA15 - button 2

• PB6 - SCL - to display

• PB7 - SDA - to display

• PC13 - led on board