circuitpython/ports/samd/mcu
robert-hh e33db80a59 samd/clock_config: Extend the SAMD51 us-counter to 60 bit.
This removes the difference in the time.ticks_us() range between SAMD21 and
SAMD51.

The function mp_hal_ticks_us_64() is added and used for:
- SAMD51's mp_hal_ticks_us and mp_hal_delay_us().
  For SAMD21, keep the previous methods, which are faster.
- mp_hal_ticks_ms() and mp_hal_tick_ms_64(), which saves some bytes
  and removes a potential race condition every 50 days.

Also set the us-counter for SAMD51 to 16 MHz for a faster reading of the
microsecond value.

Note: With SAMD51, mp_hal_ticks_us_64() has a 60 bit range only, which is
still a long time (~36000 years).
2022-10-25 23:26:14 +11:00
..
samd21 samd/machine_rtc: Add the machine.RTC class. 2022-10-25 23:20:09 +11:00
samd51 samd/clock_config: Extend the SAMD51 us-counter to 60 bit. 2022-10-25 23:26:14 +11:00