ad7172: break out mods adc, checksum, regs

master
Astro 2019-09-08 21:34:38 +02:00
parent 98a5788770
commit 8b2cc15d7d
5 changed files with 378 additions and 367 deletions

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@ -1,367 +0,0 @@
use embedded_hal::digital::v2::OutputPin;
use embedded_hal::blocking::spi::Transfer;
use byteorder::{BigEndian, ByteOrder};
use bit_field::BitField;
trait Register {
type Data: RegisterData;
fn address(&self) -> u8;
}
trait RegisterData {
fn empty() -> Self;
fn as_mut(&mut self) -> &mut [u8];
}
macro_rules! def_reg {
($Reg: ident, $reg: ident, $addr: expr, $size: expr) => {
struct $Reg;
impl Register for $Reg {
type Data = $reg::Data;
fn address(&self) -> u8 {
$addr
}
}
mod $reg {
pub struct Data(pub [u8; $size]);
impl super::RegisterData for Data {
fn empty() -> Self {
Data([0; $size])
}
fn as_mut(&mut self) -> &mut [u8] {
&mut self.0
}
}
}
};
($Reg: ident, $index: ty, $reg: ident, $addr: expr, $size: expr) => {
struct $Reg { pub index: $index, }
impl Register for $Reg {
type Data = $reg::Data;
fn address(&self) -> u8 {
$addr + (self.index as u8)
}
}
mod $reg {
pub struct Data(pub [u8; $size]);
impl super::RegisterData for Data {
fn empty() -> Self {
Data([0; $size])
}
fn as_mut(&mut self) -> &mut [u8] {
&mut self.0
}
}
}
}
}
def_reg!(Status, status, 0x00, 1);
impl status::Data {
/// Is there new data to read?
fn ready(&self) -> bool {
! self.0[0].get_bit(7)
}
/// Channel for which data is ready
fn channel(&self) -> u8 {
self.0[0].get_bits(0..=1)
}
fn adc_error(&self) -> bool {
self.0[0].get_bit(6)
}
fn crc_error(&self) -> bool {
self.0[0].get_bit(5)
}
fn reg_error(&self) -> bool {
self.0[0].get_bit(4)
}
}
def_reg!(IfMode, if_mode, 0x02, 2);
impl if_mode::Data {
fn set_crc(&mut self, mode: ChecksumMode) {
self.0[1].set_bits(2..=3, mode as u8);
}
}
def_reg!(Data, data, 0x04, 3);
impl data::Data {
fn data(&self) -> u32 {
(u32::from(self.0[0]) << 16) |
(u32::from(self.0[1]) << 8) |
u32::from(self.0[2])
}
}
def_reg!(Id, id, 0x07, 2);
impl id::Data {
fn id(&self) -> u16 {
BigEndian::read_u16(&self.0)
}
}
def_reg!(Channel, u8, channel, 0x10, 2);
impl channel::Data {
fn enabled(&self) -> bool {
self.0[0].get_bit(7)
}
fn set_enabled(&mut self, value: bool) {
self.0[0].set_bit(7, value);
}
}
def_reg!(SetupCon, u8, setup_con, 0x20, 2);
def_reg!(FiltCon, u8, filt_con, 0x80, 2);
// #[allow(unused)]
// #[derive(Clone, Copy)]
// #[repr(u8)]
// pub enum Register {
// Status = 0x00,
// AdcMode = 0x01,
// IfMode = 0x02,
// RegCheck = 0x03,
// Data = 0x04,
// GpioCon = 0x06,
// Id = 0x07,
// Ch0 = 0x10,
// Ch1 = 0x11,
// Ch2 = 0x12,
// Ch3 = 0x13,
// SetupCon0 = 0x20,
// SetupCon1 = 0x21,
// SetupCon2 = 0x22,
// SetupCon3 = 0x23,
// FiltCon0 = 0x28,
// FiltCon1 = 0x29,
// FiltCon2 = 0x2A,
// FiltCon3 = 0x2B,
// Offset0 = 0x30,
// Offset1 = 0x31,
// Offset2 = 0x32,
// Offset3 = 0x33,
// Gain0 = 0x38,
// Gain1 = 0x39,
// Gain2 = 0x3A,
// Gain3 = 0x3B,
// }
#[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,
}
#[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, PartialEq)]
#[repr(u8)]
pub enum ChecksumMode {
Off = 0b00,
/// Seems much less reliable than `Crc`
Xor = 0b01,
Crc = 0b10,
}
struct Checksum {
mode: ChecksumMode,
state: u8,
}
impl Checksum {
pub fn new(mode: ChecksumMode) -> Self {
Checksum { mode, state: 0 }
}
pub fn feed(&mut self, input: u8) {
match self.mode {
ChecksumMode::Off => {},
ChecksumMode::Xor => self.state ^= input,
ChecksumMode::Crc => {
for i in 0..8 {
let input_mask = 0x80 >> i;
self.state = (self.state << 1) ^
if ((self.state & 0x80) != 0) != ((input & input_mask) != 0) {
0x07 /* x8 + x2 + x + 1 */
} else {
0
};
}
}
}
}
pub fn result(&self) -> Option<u8> {
match self.mode {
ChecksumMode::Off => None,
_ => Some(self.state)
}
}
}
/// AD7172-2 implementation
///
/// [Manual](https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf)
pub struct Adc<SPI: Transfer<u8>, NSS: OutputPin> {
spi: SPI,
nss: NSS,
checksum_mode: ChecksumMode,
}
impl<SPI: Transfer<u8>, NSS: OutputPin> Adc<SPI, NSS> {
pub fn new(spi: SPI, mut nss: NSS) -> Result<Self, SPI::Error> {
let _ = nss.set_high();
let mut adc = Adc {
spi, nss,
checksum_mode: ChecksumMode::Off,
};
adc.reset()?;
Ok(adc)
}
/// `0x00DX` for AD7271-2
pub fn identify(&mut self) -> Result<u16, AdcError<SPI::Error>> {
self.read_reg(&Id)
.map(|id| id.id())
}
pub fn set_checksum_mode(&mut self, mode: ChecksumMode) -> Result<(), AdcError<SPI::Error>> {
let mut ifmode = self.read_reg(&IfMode)?;
ifmode.set_crc(mode);
self.checksum_mode = mode;
self.write_reg(&IfMode, &mut ifmode)?;
Ok(())
}
// pub fn setup(&mut self) -> Result<(), SPI::Error> {
// let mut buf = [0, 0, 0];
// adc.write_reg(Register::AdcMode, &mut buf)?;
// let mut buf = [0, 1, 0];
// adc.write_reg(Register::IfMode, &mut buf)?;
// let mut buf = [0, 0, 0];
// adc.write_reg(Register::GpioCon, &mut buf)?;
// Ok(())
// }
/// Returns the channel the data is from
pub fn data_ready(&mut self) -> Result<Option<u8>, AdcError<SPI::Error>> {
self.read_reg(&Status)
.map(|status| {
if status.ready() {
Some(status.channel())
} else {
None
}
})
}
/// Get data
pub fn read_data(&mut self) -> Result<u32, AdcError<SPI::Error>> {
self.read_reg(&Data)
.map(|data| data.data())
}
fn read_reg<R: Register>(&mut self, reg: &R) -> Result<R::Data, AdcError<SPI::Error>> {
let mut reg_data = R::Data::empty();
let address = 0x40 | reg.address();
let mut checksum = Checksum::new(self.checksum_mode);
checksum.feed(address);
let checksum_out = checksum.result();
let checksum_in = self.transfer(address, reg_data.as_mut(), checksum_out)?;
for &mut b in reg_data.as_mut() {
checksum.feed(b);
}
let checksum_expected = checksum.result();
if checksum_expected != checksum_in {
return Err(AdcError::ChecksumMismatch(checksum_expected, checksum_in));
}
Ok(reg_data)
}
fn write_reg<R: Register>(&mut self, reg: &R, reg_data: &mut R::Data) -> Result<(), AdcError<SPI::Error>> {
let address = reg.address();
let mut checksum = Checksum::new(match self.checksum_mode {
ChecksumMode::Off => ChecksumMode::Off,
// write checksums are always crc
ChecksumMode::Xor => ChecksumMode::Crc,
ChecksumMode::Crc => ChecksumMode::Crc,
});
checksum.feed(address);
for &mut b in reg_data.as_mut() {
checksum.feed(b);
}
let checksum_out = checksum.result();
self.transfer(address, reg_data.as_mut(), checksum_out)?;
Ok(())
}
fn update_reg<R, F, A>(&mut self, reg: &R, f: F) -> Result<A, AdcError<SPI::Error>>
where
R: Register,
F: FnOnce(&mut R::Data) -> A,
{
let mut reg_data = self.read_reg(reg)?;
let result = f(&mut reg_data);
self.write_reg(reg, &mut reg_data)?;
Ok(result)
}
pub fn reset(&mut self) -> Result<(), SPI::Error> {
let mut buf = [0xFFu8; 8];
let _ = self.nss.set_low();
let result = self.spi.transfer(&mut buf);
let _ = self.nss.set_high();
result?;
Ok(())
}
fn transfer<'w>(&mut self, addr: u8, reg_data: &'w mut [u8], checksum: Option<u8>) -> Result<Option<u8>, SPI::Error> {
let mut addr_buf = [addr];
let _ = self.nss.set_low();
let result = match self.spi.transfer(&mut addr_buf) {
Ok(_) => self.spi.transfer(reg_data),
Err(e) => Err(e),
};
let result = match (result, checksum) {
(Ok(_),None) =>
Ok(None),
(Ok(_), Some(checksum_out)) => {
let mut checksum_buf = [checksum_out; 1];
match self.spi.transfer(&mut checksum_buf) {
Ok(_) => Ok(Some(checksum_buf[0])),
Err(e) => Err(e),
}
}
(Err(e), _) =>
Err(e),
};
let _ = self.nss.set_high();
result
}
}

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firmware/src/ad7172/adc.rs Normal file
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use embedded_hal::digital::v2::OutputPin;
use embedded_hal::blocking::spi::Transfer;
use super::checksum::{ChecksumMode, Checksum};
use super::AdcError;
use super::regs::*;
/// AD7172-2 implementation
///
/// [Manual](https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf)
pub struct Adc<SPI: Transfer<u8>, NSS: OutputPin> {
spi: SPI,
nss: NSS,
checksum_mode: ChecksumMode,
}
impl<SPI: Transfer<u8>, NSS: OutputPin> Adc<SPI, NSS> {
pub fn new(spi: SPI, mut nss: NSS) -> Result<Self, SPI::Error> {
let _ = nss.set_high();
let mut adc = Adc {
spi, nss,
checksum_mode: ChecksumMode::Off,
};
adc.reset()?;
Ok(adc)
}
/// `0x00DX` for AD7271-2
pub fn identify(&mut self) -> Result<u16, AdcError<SPI::Error>> {
self.read_reg(&Id)
.map(|id| id.id())
}
pub fn set_checksum_mode(&mut self, mode: ChecksumMode) -> Result<(), AdcError<SPI::Error>> {
let mut ifmode = self.read_reg(&IfMode)?;
ifmode.set_crc(mode);
self.checksum_mode = mode;
self.write_reg(&IfMode, &mut ifmode)?;
Ok(())
}
// pub fn setup(&mut self) -> Result<(), SPI::Error> {
// let mut buf = [0, 0, 0];
// adc.write_reg(Register::AdcMode, &mut buf)?;
// let mut buf = [0, 1, 0];
// adc.write_reg(Register::IfMode, &mut buf)?;
// let mut buf = [0, 0, 0];
// adc.write_reg(Register::GpioCon, &mut buf)?;
// Ok(())
// }
/// Returns the channel the data is from
pub fn data_ready(&mut self) -> Result<Option<u8>, AdcError<SPI::Error>> {
self.read_reg(&Status)
.map(|status| {
if status.ready() {
Some(status.channel())
} else {
None
}
})
}
/// Get data
pub fn read_data(&mut self) -> Result<u32, AdcError<SPI::Error>> {
self.read_reg(&Data)
.map(|data| data.data())
}
fn read_reg<R: Register>(&mut self, reg: &R) -> Result<R::Data, AdcError<SPI::Error>> {
let mut reg_data = R::Data::empty();
let address = 0x40 | reg.address();
let mut checksum = Checksum::new(self.checksum_mode);
checksum.feed(address);
let checksum_out = checksum.result();
let checksum_in = self.transfer(address, reg_data.as_mut(), checksum_out)?;
for &mut b in reg_data.as_mut() {
checksum.feed(b);
}
let checksum_expected = checksum.result();
if checksum_expected != checksum_in {
return Err(AdcError::ChecksumMismatch(checksum_expected, checksum_in));
}
Ok(reg_data)
}
fn write_reg<R: Register>(&mut self, reg: &R, reg_data: &mut R::Data) -> Result<(), AdcError<SPI::Error>> {
let address = reg.address();
let mut checksum = Checksum::new(match self.checksum_mode {
ChecksumMode::Off => ChecksumMode::Off,
// write checksums are always crc
ChecksumMode::Xor => ChecksumMode::Crc,
ChecksumMode::Crc => ChecksumMode::Crc,
});
checksum.feed(address);
for &mut b in reg_data.as_mut() {
checksum.feed(b);
}
let checksum_out = checksum.result();
self.transfer(address, reg_data.as_mut(), checksum_out)?;
Ok(())
}
fn update_reg<R, F, A>(&mut self, reg: &R, f: F) -> Result<A, AdcError<SPI::Error>>
where
R: Register,
F: FnOnce(&mut R::Data) -> A,
{
let mut reg_data = self.read_reg(reg)?;
let result = f(&mut reg_data);
self.write_reg(reg, &mut reg_data)?;
Ok(result)
}
pub fn reset(&mut self) -> Result<(), SPI::Error> {
let mut buf = [0xFFu8; 8];
let _ = self.nss.set_low();
let result = self.spi.transfer(&mut buf);
let _ = self.nss.set_high();
result?;
Ok(())
}
fn transfer<'w>(&mut self, addr: u8, reg_data: &'w mut [u8], checksum: Option<u8>) -> Result<Option<u8>, SPI::Error> {
let mut addr_buf = [addr];
let _ = self.nss.set_low();
let result = match self.spi.transfer(&mut addr_buf) {
Ok(_) => self.spi.transfer(reg_data),
Err(e) => Err(e),
};
let result = match (result, checksum) {
(Ok(_),None) =>
Ok(None),
(Ok(_), Some(checksum_out)) => {
let mut checksum_buf = [checksum_out; 1];
match self.spi.transfer(&mut checksum_buf) {
Ok(_) => Ok(Some(checksum_buf[0])),
Err(e) => Err(e),
}
}
(Err(e), _) =>
Err(e),
};
let _ = self.nss.set_high();
result
}
}

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#[derive(Clone, Copy, PartialEq)]
#[repr(u8)]
pub enum ChecksumMode {
Off = 0b00,
/// Seems much less reliable than `Crc`
Xor = 0b01,
Crc = 0b10,
}
pub struct Checksum {
mode: ChecksumMode,
state: u8,
}
impl Checksum {
pub fn new(mode: ChecksumMode) -> Self {
Checksum { mode, state: 0 }
}
pub fn feed(&mut self, input: u8) {
match self.mode {
ChecksumMode::Off => {},
ChecksumMode::Xor => self.state ^= input,
ChecksumMode::Crc => {
for i in 0..8 {
let input_mask = 0x80 >> i;
self.state = (self.state << 1) ^
if ((self.state & 0x80) != 0) != ((input & input_mask) != 0) {
0x07 /* x8 + x2 + x + 1 */
} else {
0
};
}
}
}
}
pub fn result(&self) -> Option<u8> {
match self.mode {
ChecksumMode::Off => None,
_ => Some(self.state)
}
}
}

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mod regs;
mod checksum;
pub use checksum::ChecksumMode;
mod adc;
pub use adc::*;
#[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,
}
#[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)
}
}

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firmware/src/ad7172/regs.rs Normal file
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use byteorder::{BigEndian, ByteOrder};
use bit_field::BitField;
use super::*;
pub trait Register {
type Data: RegisterData;
fn address(&self) -> u8;
}
pub trait RegisterData {
fn empty() -> Self;
fn as_mut(&mut self) -> &mut [u8];
}
macro_rules! def_reg {
($Reg: ident, $reg: ident, $addr: expr, $size: expr) => {
pub struct $Reg;
impl Register for $Reg {
type Data = $reg::Data;
fn address(&self) -> u8 {
$addr
}
}
mod $reg {
pub struct Data(pub [u8; $size]);
impl super::RegisterData for Data {
fn empty() -> Self {
Data([0; $size])
}
fn as_mut(&mut self) -> &mut [u8] {
&mut self.0
}
}
}
};
($Reg: ident, $index: ty, $reg: ident, $addr: expr, $size: expr) => {
struct $Reg { pub index: $index, }
impl Register for $Reg {
type Data = $reg::Data;
fn address(&self) -> u8 {
$addr + (self.index as u8)
}
}
mod $reg {
pub struct Data(pub [u8; $size]);
impl super::RegisterData for Data {
fn empty() -> Self {
Data([0; $size])
}
fn as_mut(&mut self) -> &mut [u8] {
&mut self.0
}
}
}
}
}
def_reg!(Status, status, 0x00, 1);
impl status::Data {
/// Is there new data to read?
pub fn ready(&self) -> bool {
! self.0[0].get_bit(7)
}
/// Channel for which data is ready
pub fn channel(&self) -> u8 {
self.0[0].get_bits(0..=1)
}
pub fn adc_error(&self) -> bool {
self.0[0].get_bit(6)
}
pub fn crc_error(&self) -> bool {
self.0[0].get_bit(5)
}
pub fn reg_error(&self) -> bool {
self.0[0].get_bit(4)
}
}
def_reg!(IfMode, if_mode, 0x02, 2);
impl if_mode::Data {
pub fn set_crc(&mut self, mode: ChecksumMode) {
self.0[1].set_bits(2..=3, mode as u8);
}
}
def_reg!(Data, data, 0x04, 3);
impl data::Data {
pub fn data(&self) -> u32 {
(u32::from(self.0[0]) << 16) |
(u32::from(self.0[1]) << 8) |
u32::from(self.0[2])
}
}
def_reg!(Id, id, 0x07, 2);
impl id::Data {
pub fn id(&self) -> u16 {
BigEndian::read_u16(&self.0)
}
}
def_reg!(Channel, u8, channel, 0x10, 2);
impl channel::Data {
pub fn enabled(&self) -> bool {
self.0[0].get_bit(7)
}
pub fn set_enabled(&mut self, value: bool) {
self.0[0].set_bit(7, value);
}
}
def_reg!(SetupCon, u8, setup_con, 0x20, 2);
def_reg!(FiltCon, u8, filt_con, 0x80, 2);
// #[allow(unused)]
// #[derive(Clone, Copy)]
// #[repr(u8)]
// pub enum Register {
// Status = 0x00,
// AdcMode = 0x01,
// IfMode = 0x02,
// RegCheck = 0x03,
// Data = 0x04,
// GpioCon = 0x06,
// Id = 0x07,
// Ch0 = 0x10,
// Ch1 = 0x11,
// Ch2 = 0x12,
// Ch3 = 0x13,
// SetupCon0 = 0x20,
// SetupCon1 = 0x21,
// SetupCon2 = 0x22,
// SetupCon3 = 0x23,
// FiltCon0 = 0x28,
// FiltCon1 = 0x29,
// FiltCon2 = 0x2A,
// FiltCon3 = 0x2B,
// Offset0 = 0x30,
// Offset1 = 0x31,
// Offset2 = 0x32,
// Offset3 = 0x33,
// Gain0 = 0x38,
// Gain1 = 0x39,
// Gain2 = 0x3A,
// Gain3 = 0x3B,
// }