thermostat/src/ad7172/mod.rs

205 lines
4.8 KiB
Rust
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use core::fmt;
use num_traits::float::Float;
use stm32f4xx_hal::{
time::{MegaHertz, U32Ext},
spi,
};
pub mod regs;
mod checksum;
pub use checksum::ChecksumMode;
mod adc;
pub use adc::*;
/// SPI Mode 3
pub const SPI_MODE: spi::Mode = spi::Mode {
polarity: spi::Polarity::IdleHigh,
phase: spi::Phase::CaptureOnSecondTransition,
};
/// 2 MHz
pub const SPI_CLOCK: MegaHertz = MegaHertz(2);
pub const MAX_VALUE: u32 = 0xFF_FFFF;
#[derive(Clone, Debug, PartialEq)]
pub enum AdcError<SPI> {
SPI(SPI),
ChecksumMismatch(Option<u8>, Option<u8>),
}
impl<SPI> From<SPI> for AdcError<SPI> {
fn from(e: SPI) -> Self {
AdcError::SPI(e)
}
}
#[derive(Clone, Copy, Debug)]
#[repr(u8)]
pub enum Input {
Ain0 = 0,
Ain1 = 1,
Ain2 = 2,
Ain3 = 3,
Ain4 = 4,
TemperaturePos = 17,
TemperatureNeg = 18,
AnalogSupplyPos = 19,
AnalogSupplyNeg = 20,
RefPos = 21,
RefNeg = 22,
Invalid = 0b11111,
}
impl From<u8> for Input {
fn from(x: u8) -> Self {
match x {
0 => Input::Ain0,
1 => Input::Ain1,
2 => Input::Ain2,
3 => Input::Ain3,
4 => Input::Ain4,
17 => Input::TemperaturePos,
18 => Input::TemperatureNeg,
19 => Input::AnalogSupplyPos,
20 => Input::AnalogSupplyNeg,
21 => Input::RefPos,
22 => Input::RefNeg,
_ => Input::Invalid,
}
}
}
impl fmt::Display for Input {
fn fmt(&self, fmt: &mut fmt::Formatter) -> Result<(), fmt::Error> {
use Input::*;
match self {
Ain0 => "ain0",
Ain1 => "ain1",
Ain2 => "ain2",
Ain3 => "ain3",
Ain4 => "ain4",
TemperaturePos => "temperature+",
TemperatureNeg => "temperature-",
AnalogSupplyPos => "analogsupply+",
AnalogSupplyNeg => "analogsupply-",
RefPos => "ref+",
RefNeg => "ref-",
_ => "<INVALID>",
}.fmt(fmt)
}
}
/// Reference source for ADC conversion
#[repr(u8)]
pub enum RefSource {
/// External reference
External = 0b00,
/// Internal 2.5V reference
Internal = 0b10,
/// AVDD1 AVSS
Avdd1MinusAvss = 0b11,
Invalid = 0b01,
}
impl From<u8> for RefSource {
fn from(x: u8) -> Self {
match x {
0 => RefSource::External,
1 => RefSource::Internal,
2 => RefSource::Avdd1MinusAvss,
_ => RefSource::Invalid,
}
}
}
impl fmt::Display for RefSource {
fn fmt(&self, fmt: &mut fmt::Formatter) -> Result<(), fmt::Error> {
use RefSource::*;
match self {
External => "external",
Internal => "internal",
Avdd1MinusAvss => "avdd1-avss",
_ => "<INVALID>",
}.fmt(fmt)
}
}
#[derive(Clone, Copy)]
#[repr(u8)]
pub enum PostFilter {
/// 27 SPS, 47 dB rejection, 36.7 ms settling
F27SPS = 0b010,
/// 21.25 SPS, 62 dB rejection, 40 ms settling
F21SPS = 0b011,
/// 20 SPS, 86 dB rejection, 50 ms settling
F20SPS = 0b101,
/// 16.67 SPS, 92 dB rejection, 60 ms settling
F16SPS = 0b110,
Invalid = 0b111,
}
impl PostFilter {
pub const VALID_VALUES: &'static [Self] = &[
PostFilter::F27SPS,
PostFilter::F21SPS,
PostFilter::F20SPS,
PostFilter::F16SPS,
];
pub fn closest(rate: f32) -> Option<Self> {
let mut best: Option<(f32, Self)> = None;
for value in Self::VALID_VALUES {
let error = (rate - value.output_rate().unwrap()).abs();
let better = best
.map(|(best_error, _)| error < best_error)
.unwrap_or(true);
if better {
best = Some((error, *value));
}
}
best.map(|(_, best)| best)
}
/// Samples per Second
pub fn output_rate(&self) -> Option<f32> {
match self {
PostFilter::F27SPS => Some(27.0),
PostFilter::F21SPS => Some(21.25),
PostFilter::F20SPS => Some(20.0),
PostFilter::F16SPS => Some(16.67),
PostFilter::Invalid => None,
}
}
}
impl From<u8> for PostFilter {
fn from(x: u8) -> Self {
match x {
0b010 => PostFilter::F27SPS,
0b011 => PostFilter::F21SPS,
0b101 => PostFilter::F20SPS,
0b110 => PostFilter::F16SPS,
_ => PostFilter::Invalid,
}
}
}
#[repr(u8)]
pub enum DigitalFilterOrder {
Sinc5Sinc1 = 0b00,
Sinc3 = 0b11,
Invalid = 0b10,
}
impl From<u8> for DigitalFilterOrder {
fn from(x: u8) -> Self {
match x {
0b00 => DigitalFilterOrder::Sinc5Sinc1,
0b11 => DigitalFilterOrder::Sinc3,
_ => DigitalFilterOrder::Invalid,
}
}
}