[Snek] [keith-packard/snek] d2c37e: chips/samd21: Allow PWM values to adjust slowly ra...

[Keith Packard]

  Branch: refs/heads/master
  Home:   https://github.com/keith-packard/snek
  Commit: d2c37e47ac4b7031dcbe280c737c5d0355ed336e
      https://github.com/keith-packard/snek/commit/d2c37e47ac4b7031dcbe280c737c5d0355ed336e
  Author: Keith Packard <keithp at keithp.com>
  Date:   2019-07-09 (Tue, 09 Jul 2019)

  Changed paths:
    M chips/samd21/ao-snek.h
    M chips/samd21/ao-timer.c
    M chips/samd21/snek-gpio.c
    M ports/snekboard/ao-pins.h

  Log Message:
  -----------
  chips/samd21: Allow PWM values to adjust slowly rather than jump

To reduce current demand and reduce motor wear, ramp PWM values
slowly in a timer hook.

Signed-off-by: Keith Packard <keithp at keithp.com>


  Commit: 9b93d9afe115bef889d5f50ee6cb1f119fc9b228
      https://github.com/keith-packard/snek/commit/9b93d9afe115bef889d5f50ee6cb1f119fc9b228
  Author: Keith Packard <keithp at keithp.com>
  Date:   2019-07-20 (Sat, 20 Jul 2019)

  Changed paths:
    M ao/ao.h
    M chips/samd21/ao-timer.c

  Log Message:
  -----------
  samd21: Switch ticks to 1kHz

This provides finer sleep resolution

Signed-off-by: Keith Packard <keithp at keithp.com>


  Commit: b55589a176c61c27d5e16f96ba18352ea7f088f5
      https://github.com/keith-packard/snek/commit/b55589a176c61c27d5e16f96ba18352ea7f088f5
  Author: Keith Packard <keithp at keithp.com>
  Date:   2019-07-20 (Sat, 20 Jul 2019)

  Changed paths:
    M chips/samd21/snek-gpio.c

  Log Message:
  -----------
  chips/samd21: Make ramp-pwm code include dir

This makes setleft/setright also ramp smoothly between the speeds to
reduce motor current spikes.

Signed-off-by: Keith Packard <keithp at keithp.com>


  Commit: a86a294191226040e54de9309264f6279fb4a5b8
      https://github.com/keith-packard/snek/commit/a86a294191226040e54de9309264f6279fb4a5b8
  Author: Keith Packard <keithp at keithp.com>
  Date:   2019-07-20 (Sat, 20 Jul 2019)

  Changed paths:
    M ports/snekboard/ao-pins.h

  Log Message:
  -----------
  ports/snekboard: Slow PWM ramp by half to keep power supply happy

This value is experimentally discovered to keep the 3.3V rail running
smoothly when turning motors on/off.

Signed-off-by: Keith Packard <keithp at keithp.com>


Compare: https://github.com/keith-packard/snek/compare/18eff787351f...a86a29419122