Teensy 4 FlexTimer Module (FTM) / Quad Timer (QTIMER) Input Capture capabilities
Just in case somebody has already dug out relevant specs:
I am using Teensy 3.x for FTM input capture, targeting bursts of pulses at modulation frequencies between 1.8MHz and 10MHz, with burst O(10-100) pulses repeated at varying intervals with an average repeat rate of 120 bursts/sec to 400 bursts/sec. There are multiple of these inputs, I am handling up to 8 of these on a Teensy 3.x.
There are two different modulation types I need to handle:
* One is constant carrier frequency per burst, but could vary from one burst to the next.
* The other is an LFSR / Manchester modulation, e.g. a 3/6 MHz FSK
https://github.com/cnlohr/esptracker/issues/1#issuecomment-410804130
What I ultimately need is an MCU capturing 20+ inputs, with 48/60/more MHz FTM, distinguishing rising and failing edge of each modulation pulse.
What FTM sampling frequency does Teensy4 support?
How many concurrent FTM inputs can it service?
Can it distinguish rising and falling on a single input?
What kind of CPU load as a function of N_inputs * N_pulses/burst * N_avg_bursts/second ?
Thanks!
Just in case somebody has already dug out relevant specs:
I am using Teensy 3.x for FTM input capture, targeting bursts of pulses at modulation frequencies between 1.8MHz and 10MHz, with burst O(10-100) pulses repeated at varying intervals with an average repeat rate of 120 bursts/sec to 400 bursts/sec. There are multiple of these inputs, I am handling up to 8 of these on a Teensy 3.x.
There are two different modulation types I need to handle:
* One is constant carrier frequency per burst, but could vary from one burst to the next.
* The other is an LFSR / Manchester modulation, e.g. a 3/6 MHz FSK
https://github.com/cnlohr/esptracker/issues/1#issuecomment-410804130
What I ultimately need is an MCU capturing 20+ inputs, with 48/60/more MHz FTM, distinguishing rising and failing edge of each modulation pulse.
What FTM sampling frequency does Teensy4 support?
How many concurrent FTM inputs can it service?
Can it distinguish rising and falling on a single input?
What kind of CPU load as a function of N_inputs * N_pulses/burst * N_avg_bursts/second ?
Thanks!
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