Commit Graph

4 Commits

Author SHA1 Message Date
robert-hh
e69313f89c samd: Add a vref=num option to the ADC and DAC constructor.
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).
2022-12-14 12:48:24 +11:00
robert-hh
4d38ab652e samd: Make ADC, DAC, PWM, SPI objects consistent in how they print out.
All of ADC, DAC, Pin, PWM and SPI looked different before this change.
2022-10-25 23:36:01 +11:00
robert-hh
e5cf3fab95 samd/machine_pin: Change the pin handling and naming/numbering.
Pin numbers are now the MCU port numbers in the range:

    PA0..PA31:  0..31
    PB0..PB31: 32..63
    PC0..PC31: 64..95
    PD0..PD31: 96..127

Pins can be denoted by the GPIO port number, the name as defined in
pins.csv or a string in the form Pxnn, like "PA16" or "PD03".

The pins.c and pins.h files are now obsolete.  The pin objects are part of
the AF table.

As result of a simplification, the code now supports using pin names or
numbers instead of pin objects for modules like UART, SPI, PWM, I2C, ADC,
pininfo.
2022-10-25 23:34:07 +11:00
robert-hh
5c7e93ec48 samd/machine_adc: Add the machine.ADC class.
With the method read_u16().  Keyword arguments of the constructor are:
- bits=n    The resolution; default is 12.
- average=n The average of samples, which are taken and cumulated.  The
            default value is 16.  Averaging by hw is faster than averaging
            in code.

The ADC runs at a clock freq 1.5 MHz.  A single 12 bit conversion takes
8 microseconds.
2022-10-06 22:41:44 +11:00