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Description of our implementation of VHT:

• HF: for the low frequency the GPTimer from the simplelink SDK is used, this timer uses the 48 MHZ clock
• LF: for this several ideas exist:

1. using CH2 from the RTC in the Continuous compare mode (interrupt can happen every 2 cycles)
2. using the 32KHZ signal from the AON crystal
3. using CH1 compare and doing the increment by software manually
4. using the AUX timer

for the time being, option 3 is used. But instead of the interrupt happening with every LF clock rising edge as mentioned in the VHT paper, the interrupt happens every 8th cycle. Still, this is good enough for glossy to work, proof: the clock drift for the 32KHZ clock is 20 ppm and for the 48MHZ is 10 ppm (as mentioned here). from the ratio between the two clocks, we can find the 8 LF cycles equal 12000 HF cycles and as the clock drift for the HF is 10 ppm then the 12000 have a drift of 0.012 cycle. And as one HF cycle takes 20.83 ns then the drift results in 0.24996 ns and this is still within glossy limits as mentioned in the glossy paper and still much less expensive than the time needed for code execution.