single phase QDEC ?

RE: single phase QDEC ?

Sigurd — Mon, 14 Aug 2017 10:49:50 GMT

Yes,

If you want to measure the time/duration between each pulse, you should use the TIMER peripheral in Timer mode. If you only need to count and keep track of the number of pulses, then use the LowPowerCounter mode.

RE: single phase QDEC ?

Thiru — Sun, 13 Aug 2017 20:55:14 GMT

so you suggestion is use falling edge or rising edge , use PPI event to start and stop the timer, get the duration, this duration will be the time for one rotation.

anyway i can use any counter to count pulse in the pin

RE: single phase QDEC ?

Sigurd — Wed, 09 Aug 2017 12:04:14 GMT

Hi,

The QDEC peripheral is designed for two-phase inputs. You could in theory use it count a single phase by assigning the same GPIO pin where your phase is to both Phase A and Phase B inputs. You will then get what’s called a double transition (invalid sample), and you can read the count result from the ACCDBL register. Note that the ACCDBL is just a 4 bit register, while the normal(valid samples) ACC register is 32 bit.

Since this is just a single phase, a more suited approach might be to just simply use the TIMER and GPIOTE. The GPIOTE can be configured to generate an event on a pin change, and using the PPI you can connect that event to the TIMER running in LowPowerCounter mode.