Looking for TimerOne.h or similar

I'm looking for a TimerOne.h library or similar that works with the new SAMD nanod. I want to do variable speed control of 2 stepper motors in the timer whilst doing some maths stuff (IMU/PID) in the main loop which sets the appropriate stepper speed.

TimerOne.h isn't for SAMD architecture - I tried a couple of the samd timer libraries e.g. avdweb_SAMDtimer (which uses Adafruit_ZeroTimer.h) but had problems with a missing type 'tc_callback_t'.

Anyone got any examples of how to do this sort of thing? I've seem some tutorials on using low level timer interrups (ISR functions with prescalers) but I don't think I'd get this working without knowing all the freaky memory addresses specific to the nano.

I love the hardware on these new boards but I wasn't expecting things like timer1 to be unavailable.

Answering my own question, the IOT 33 is similar to the mkr 1010 which unfortunately doesn't suppotr Interrupt Service Routines (ISRs).

I'm trying out the Timer5 library that is discussed here: https://forum.arduino.cc/index.php?topic=422821.0

It compiles and works - seems to offer a 'frequency/hz' interrupt rather than a 'time/μs' interrupt. I'm using it 'as is' which offers 1hz to 16384hz (32khz doesn't work for me) or there is an option to switch to the 48Mhz oscillator which gives a lowest frequency of 1464Hz (48Mhz/2^15) up to presumably 24Mhz but at this speed its so 'interrupty' that simple Serial.println in main loop() no longer work.

The Timer5 is hardcoded with a prescaler of 1 but this can be shifted up to 16 i.e. that base 1464Hz could be shifted to ~92Hz

Timer5 could do with a few Pull Requests to make it more flexible. I might give it a go if I can find the time.

Maybe these can be helpful? https://github.com/adafruit/Adafruit_ZeroTimer and https://github.com/avandalen/avdweb_SAMDtimer