Back to: Gait_Measurement_Timer

'Misc. Notes

Plastic Sensor PCB Mounting Spacers: round 4-40 length .345 inches

The schematic for the IR sensor should have the correct labels for the LEDs.

Push-button switch assignments:

1 = set hours (MOM_SWS pin 1,2)

2 = set minutes (MOM_SWS pin 3,4)

4 = reset (MOM_SWS pin 5,6)


The posted software for the IR sensor board may have the wrong freq for the LED pulsing. There is some confusion over 38KHz vs 40KHz depending on which IR receiver is actually installed. Perhaps it is necessary to test both.

'Firmware Programming

A hex file is needed. 'gait_timer.hex for the main unit and 'gait_sensor_38.hex for the sensor unit.

To program the sensor, ensure power is on pins 1, 2 (5V, GND) of RJ-45:

  sudo avrdude -p t45 -c avrusb500 -e -U flash:w:gait_sensor_38.hex 

To program the main unit, connect the AC adapter and turn it on. Then:

  sudo avrdude -p m8 -c avrusb500 -e -U flash:w:gait_timer.hex

Also, the AVR fuses must be programmed to select the 4MHz crystal oscillator option:

  sudo avrdude -p m8 -c avrusb500 -t

  w lfuse 0 0xef

Last modified 10 years ago Last modified on Nov 8, 2013, 10:17:54 AM