adc

type ADC ¶

type ADC interface {
	// OutputCode queries the channel and returns its digital output code.
	// This should be the raw value. If exists, PGA should not be applied.
	OutputCode(channel int) (int, error)
	// Voltage queries the channel of an ADC and returns its voltage.
	Voltage(channel int) (float64, error)
}

ADC is the interface that wraps an OutputCode and Voltage method. The first returns the digital output code of a channel. The latter returns the voltage of a channel.

type InputType ¶

type InputType int

InputType defines how an ADC samples the input signal. A single-ended input samples its input in the range from the ground (0V) to Vref, that is the reference input. A 10-bits ADC with a reference input of 5V has a precision of (5 - 0) / 1024 = 0.0049V = 4.9mV on single-ended inputs.

A (pseudo-)differential output input samples its input between voltage of a second pin and Vref, allowing measurements with higher precision. Assume a voltage on that second pin is 3V and Vref is 5V. That gives a precision of (5 - 3) / 1024 = 0.0020V = 2.0mV for measurements between 3V and 5V. Of course, values between 0V and 3V cannot be measured in this case.

const (
	// SingleEnded configures the inputs of an ADC as single-ended.
	SingleEnded InputType = 0

	// PseudoDifferential configures the inputs of an ADC as pseudo-differential.
	PseudoDifferential InputType = 1
)