These include ADC, DAC, I2C, SoftI2C, SPI, SoftI2C, PWM, UART, pulse. This
is useful for devices like the Adafruit Trinket series which have almost no
accessible GPIO pins.
Signed-off-by: robert-hh <robert@hammelrath.com>
ADC: The argument of vref=num is an integer. Values for num are:
SAMD21:
0 INT1V 1.0V voltage reference
1 INTVCC0 1/1.48 Analog voltage supply
2 INTVCC1 1/2 Analog voltage supply (only for VDDANA > 2.0V)
3 VREFA External reference
4 VREFB External reference
SAMD51:
0 INTREF internal bandgap reference
1 INTVCC1 Analog voltage supply
2 INTVCC0 1/2 Analog voltage supply (only for VDDANA > 2.0v)
3 AREFA External reference A
4 AREFB External reference B
5 AREFC External reference C (ADC1 only)
DAC: The argument of vref=num is an integer. Suitable values:
SAMD21:
0 INT1V Internal voltage reference
1 VDDANA Analog voltage supply
2 VREFA External reference
SAMD51:
0 INTREF Internal bandgap reference
1 VDDANA Analog voltage supply
2 VREFAU Unbuffered external voltage reference (not buffered in DAC)
4 VREFAB Buffered external voltage reference (buffered in DAC).
It suuports 1 channel @ 10 bit for SAMD21, 2 channels @ 12 bit for SAMD51.
Instantiation by:
dac = machine.DAC(ch) # 0 or 1
Method write:
dac.write(value)
The output voltage range is 0..Vdd.
