Can use direct control of IR LED/Sensor (without separate microcontroller?)

Here is a possible outline:

• Interrupt at 80kHz
  • Toggle IR outputs
  • count to 80
• Every 1ms
  • Check sensor status and update state
  • count to 10
• Every 10ms
  • Check buttons and update state
  • count to 10
• Every 100ms
  • Update display based on state

When timer is running, should try to update LCD in a smart' fashion as fast as possible for a good effect.

Need to control alignment LEDs for sensors, and beeper too.