embassy/embassy-stm32/src/adc/v3.rs
2022-07-27 14:13:59 +03:00

432 lines
13 KiB
Rust

use core::marker::PhantomData;
use embassy_hal_common::into_ref;
use embedded_hal_02::blocking::delay::DelayUs;
use crate::adc::{AdcPin, Instance};
use crate::Peripheral;
/// Default VREF voltage used for sample conversion to millivolts.
pub const VREF_DEFAULT_MV: u32 = 3300;
/// VREF voltage used for factory calibration of VREFINTCAL register.
pub const VREF_CALIB_MV: u32 = 3000;
/// Sadly we cannot use `RccPeripheral::enable` since devices are quite inconsistent ADC clock
/// configuration.
fn enable() {
critical_section::with(|_| unsafe {
#[cfg(stm32h7)]
crate::pac::RCC.apb2enr().modify(|w| w.set_adcen(true));
#[cfg(stm32g0)]
crate::pac::RCC.apbenr2().modify(|w| w.set_adcen(true));
#[cfg(any(stm32l4, stm32l5, stm32wb))]
crate::pac::RCC.ahb2enr().modify(|w| w.set_adcen(true));
});
}
pub enum Resolution {
TwelveBit,
TenBit,
EightBit,
SixBit,
}
impl Default for Resolution {
fn default() -> Self {
Self::TwelveBit
}
}
impl Resolution {
fn res(&self) -> crate::pac::adc::vals::Res {
match self {
Resolution::TwelveBit => crate::pac::adc::vals::Res::TWELVEBIT,
Resolution::TenBit => crate::pac::adc::vals::Res::TENBIT,
Resolution::EightBit => crate::pac::adc::vals::Res::EIGHTBIT,
Resolution::SixBit => crate::pac::adc::vals::Res::SIXBIT,
}
}
pub fn to_max_count(&self) -> u32 {
match self {
Resolution::TwelveBit => (1 << 12) - 1,
Resolution::TenBit => (1 << 10) - 1,
Resolution::EightBit => (1 << 8) - 1,
Resolution::SixBit => (1 << 6) - 1,
}
}
}
pub struct VrefInt;
impl<T: Instance> AdcPin<T> for VrefInt {}
impl<T: Instance> super::sealed::AdcPin<T> for VrefInt {
fn channel(&self) -> u8 {
#[cfg(not(stm32g0))]
let val = 0;
#[cfg(stm32g0)]
let val = 13;
val
}
}
pub struct Temperature;
impl<T: Instance> AdcPin<T> for Temperature {}
impl<T: Instance> super::sealed::AdcPin<T> for Temperature {
fn channel(&self) -> u8 {
#[cfg(not(stm32g0))]
let val = 17;
#[cfg(stm32g0)]
let val = 12;
val
}
}
pub struct Vbat;
impl<T: Instance> AdcPin<T> for Vbat {}
impl<T: Instance> super::sealed::AdcPin<T> for Vbat {
fn channel(&self) -> u8 {
#[cfg(not(stm32g0))]
let val = 18;
#[cfg(stm32g0)]
let val = 14;
val
}
}
#[cfg(not(adc_g0))]
mod sample_time {
/// ADC sample time
///
/// The default setting is 2.5 ADC clock cycles.
#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd)]
pub enum SampleTime {
/// 2.5 ADC clock cycles
Cycles2_5 = 0b000,
/// 6.5 ADC clock cycles
Cycles6_5 = 0b001,
/// 12.5 ADC clock cycles
Cycles12_5 = 0b010,
/// 24.5 ADC clock cycles
Cycles24_5 = 0b011,
/// 47.5 ADC clock cycles
Cycles47_5 = 0b100,
/// 92.5 ADC clock cycles
Cycles92_5 = 0b101,
/// 247.5 ADC clock cycles
Cycles247_5 = 0b110,
/// 640.5 ADC clock cycles
Cycles640_5 = 0b111,
}
impl SampleTime {
pub(crate) fn sample_time(&self) -> crate::pac::adc::vals::SampleTime {
match self {
SampleTime::Cycles2_5 => crate::pac::adc::vals::SampleTime::CYCLES2_5,
SampleTime::Cycles6_5 => crate::pac::adc::vals::SampleTime::CYCLES6_5,
SampleTime::Cycles12_5 => crate::pac::adc::vals::SampleTime::CYCLES12_5,
SampleTime::Cycles24_5 => crate::pac::adc::vals::SampleTime::CYCLES24_5,
SampleTime::Cycles47_5 => crate::pac::adc::vals::SampleTime::CYCLES47_5,
SampleTime::Cycles92_5 => crate::pac::adc::vals::SampleTime::CYCLES92_5,
SampleTime::Cycles247_5 => crate::pac::adc::vals::SampleTime::CYCLES247_5,
SampleTime::Cycles640_5 => crate::pac::adc::vals::SampleTime::CYCLES640_5,
}
}
}
impl Default for SampleTime {
fn default() -> Self {
Self::Cycles2_5
}
}
}
#[cfg(adc_g0)]
mod sample_time {
/// ADC sample time
///
/// The default setting is 1.5 ADC clock cycles.
#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd)]
pub enum SampleTime {
/// 1.5 ADC clock cycles
Cycles1_5 = 0b000,
/// 3.5 ADC clock cycles
Cycles3_5 = 0b001,
/// 7.5 ADC clock cycles
Cycles7_5 = 0b010,
/// 12.5 ADC clock cycles
Cycles12_5 = 0b011,
/// 19.5 ADC clock cycles
Cycles19_5 = 0b100,
/// 39.5 ADC clock cycles
Cycles39_5 = 0b101,
/// 79.5 ADC clock cycles
Cycles79_5 = 0b110,
/// 160.5 ADC clock cycles
Cycles160_5 = 0b111,
}
impl SampleTime {
pub(crate) fn sample_time(&self) -> crate::pac::adc::vals::SampleTime {
match self {
SampleTime::Cycles1_5 => crate::pac::adc::vals::SampleTime::CYCLES1_5,
SampleTime::Cycles3_5 => crate::pac::adc::vals::SampleTime::CYCLES3_5,
SampleTime::Cycles7_5 => crate::pac::adc::vals::SampleTime::CYCLES7_5,
SampleTime::Cycles12_5 => crate::pac::adc::vals::SampleTime::CYCLES12_5,
SampleTime::Cycles19_5 => crate::pac::adc::vals::SampleTime::CYCLES19_5,
SampleTime::Cycles39_5 => crate::pac::adc::vals::SampleTime::CYCLES39_5,
SampleTime::Cycles79_5 => crate::pac::adc::vals::SampleTime::CYCLES79_5,
SampleTime::Cycles160_5 => crate::pac::adc::vals::SampleTime::CYCLES160_5,
}
}
}
impl Default for SampleTime {
fn default() -> Self {
Self::Cycles1_5
}
}
}
pub use sample_time::SampleTime;
pub struct Adc<'d, T: Instance> {
sample_time: SampleTime,
vref_mv: u32,
resolution: Resolution,
phantom: PhantomData<&'d mut T>,
}
impl<'d, T: Instance> Adc<'d, T> {
pub fn new(_peri: impl Peripheral<P = T> + 'd, delay: &mut impl DelayUs<u32>) -> Self {
into_ref!(_peri);
enable();
unsafe {
T::regs().cr().modify(|reg| {
#[cfg(not(adc_g0))]
reg.set_deeppwd(false);
reg.set_advregen(true);
});
#[cfg(adc_g0)]
T::regs().cfgr1().modify(|reg| {
reg.set_chselrmod(true);
});
}
delay.delay_us(20);
unsafe {
T::regs().cr().modify(|reg| {
reg.set_adcal(true);
});
while T::regs().cr().read().adcal() {
// spin
}
}
delay.delay_us(1);
Self {
sample_time: Default::default(),
resolution: Resolution::default(),
vref_mv: VREF_DEFAULT_MV,
phantom: PhantomData,
}
}
pub fn enable_vrefint(&self, delay: &mut impl DelayUs<u32>) -> VrefInt {
unsafe {
T::common_regs().ccr().modify(|reg| {
reg.set_vrefen(true);
});
}
// "Table 24. Embedded internal voltage reference" states that it takes a maximum of 12 us
// to stabilize the internal voltage reference, we wait a little more.
// TODO: delay 15us
//cortex_m::asm::delay(20_000_000);
delay.delay_us(15);
VrefInt {}
}
pub fn enable_temperature(&self) -> Temperature {
unsafe {
T::common_regs().ccr().modify(|reg| {
reg.set_ch17sel(true);
});
}
Temperature {}
}
pub fn enable_vbat(&self) -> Vbat {
unsafe {
T::common_regs().ccr().modify(|reg| {
reg.set_ch18sel(true);
});
}
Vbat {}
}
/// Calculates the system VDDA by sampling the internal VREFINT channel and comparing
/// the result with the value stored at the factory. If the chip's VDDA is not stable, run
/// this before each ADC conversion.
#[cfg(not(stm32g0))] // TODO is this supposed to be public?
#[allow(unused)] // TODO is this supposed to be public?
fn calibrate(&mut self, vrefint: &mut VrefInt) {
#[cfg(stm32l5)]
let vrefint_cal: u32 = todo!();
#[cfg(not(stm32l5))]
let vrefint_cal = unsafe { crate::pac::VREFINTCAL.data().read().value() };
let old_sample_time = self.sample_time;
// "Table 24. Embedded internal voltage reference" states that the sample time needs to be
// at a minimum 4 us. With 640.5 ADC cycles we have a minimum of 8 us at 80 MHz, leaving
// some headroom.
self.sample_time = SampleTime::Cycles640_5;
// This can't actually fail, it's just in a result to satisfy hal trait
let vrefint_samp = self.read(vrefint);
self.sample_time = old_sample_time;
self.vref_mv = (VREF_CALIB_MV * u32::from(vrefint_cal)) / u32::from(vrefint_samp);
}
pub fn set_sample_time(&mut self, sample_time: SampleTime) {
self.sample_time = sample_time;
}
pub fn set_resolution(&mut self, resolution: Resolution) {
self.resolution = resolution;
}
/// Set VREF value in millivolts. This value is used for [to_millivolts()] sample conversion.
///
/// Use this if you have a known precise VREF (VDDA) pin reference voltage.
pub fn set_vref_mv(&mut self, vref_mv: u32) {
self.vref_mv = vref_mv;
}
/// Convert a measurement to millivolts
pub fn to_millivolts(&self, sample: u16) -> u16 {
((u32::from(sample) * self.vref_mv) / self.resolution.to_max_count()) as u16
}
/*
/// Convert a raw sample from the `Temperature` to deg C
pub fn to_degrees_centigrade(sample: u16) -> f32 {
(130.0 - 30.0) / (VtempCal130::get().read() as f32 - VtempCal30::get().read() as f32)
* (sample as f32 - VtempCal30::get().read() as f32)
+ 30.0
}
*/
/// Perform a single conversion.
fn convert(&mut self) -> u16 {
unsafe {
T::regs().isr().modify(|reg| {
reg.set_eos(true);
reg.set_eoc(true);
});
// Start conversion
T::regs().cr().modify(|reg| {
reg.set_adstart(true);
});
while !T::regs().isr().read().eos() {
// spin
}
T::regs().dr().read().0 as u16
}
}
pub fn read(&mut self, pin: &mut impl AdcPin<T>) -> u16 {
unsafe {
// Make sure bits are off
while T::regs().cr().read().addis() {
// spin
}
// Enable ADC
T::regs().isr().modify(|reg| {
reg.set_adrdy(true);
});
T::regs().cr().modify(|reg| {
reg.set_aden(true);
});
while !T::regs().isr().read().adrdy() {
// spin
}
// Configure ADC
#[cfg(not(stm32g0))]
T::regs().cfgr().modify(|reg| reg.set_res(self.resolution.res()));
#[cfg(stm32g0)]
T::regs().cfgr1().modify(|reg| reg.set_res(self.resolution.res()));
// Configure channel
Self::set_channel_sample_time(pin.channel(), self.sample_time);
// Select channel
#[cfg(not(stm32g0))]
T::regs().sqr1().write(|reg| reg.set_sq(0, pin.channel()));
#[cfg(stm32g0)]
T::regs().chselr().write(|reg| reg.set_chsel(pin.channel() as u32));
// Some models are affected by an erratum:
// If we perform conversions slower than 1 kHz, the first read ADC value can be
// corrupted, so we discard it and measure again.
//
// STM32L471xx: Section 2.7.3
// STM32G4: Section 2.7.3
#[cfg(any(rcc_l4, rcc_g4))]
let _ = self.convert();
let val = self.convert();
T::regs().cr().modify(|reg| reg.set_addis(true));
val
}
}
#[cfg(stm32g0)]
unsafe fn set_channel_sample_time(_ch: u8, sample_time: SampleTime) {
T::regs().smpr().modify(|reg| reg.set_smp1(sample_time.sample_time()));
}
#[cfg(not(stm32g0))]
unsafe fn set_channel_sample_time(ch: u8, sample_time: SampleTime) {
if ch <= 9 {
T::regs()
.smpr1()
.modify(|reg| reg.set_smp(ch as _, sample_time.sample_time()));
} else {
T::regs()
.smpr2()
.modify(|reg| reg.set_smp((ch - 10) as _, sample_time.sample_time()));
}
}
}