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heizung.rs 20.82 KiB
#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]

use core::sync::atomic::*;

use defmt::*;
use embassy_executor::Spawner;
//use embassy_futures::join::join;
use embassy_futures::select::*;
use embassy_rp::adc::{self, Adc};
use embassy_rp::peripherals::*;
use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
use embassy_sync::mutex::Mutex;
use embassy_time::{Duration, Timer, Instant};
use embassy_rp::gpio::{Input, Level, Output, Pull, Flex};
use embassy_rp::i2c;
use embassy_rp::interrupt;
//use embedded_hal_async::i2c::I2c;
use embassy_embedded_hal::SetConfig;
use embassy_rp::uart::{self, Parity};
use embassy_rp::pwm::{self, Pwm};
use {defmt_rtt as _, panic_probe as _};
use heapless::String;

use heizung::i2c_scan::{self, ScanResultForBus};
use heizung::modbus_server::{ModbusServer, ModbusRegisters, ModbusErrorCode};
use heizung::rs485::RS485;

#[embassy_executor::task]
async fn i2c_task(mut i2c_peri: embassy_rp::peripherals::I2C0,
        mut scl: embassy_rp::peripherals::PIN_13, mut sda: embassy_rp::peripherals::PIN_12,
        mut i2c_irq: embassy_rp::interrupt::I2C0_IRQ, i2c_config: i2c::Config) {
    let mut prev_scan_result = ScanResultForBus::new();
    loop {
        if true {
            let _i2c = i2c::I2c::new_async(&mut i2c_peri, &mut scl, &mut sda, &mut i2c_irq, i2c_config);
        }

        let scan_result = ScanResultForBus::scan(&mut scl, &mut sda).await;
        if prev_scan_result != scan_result {
            prev_scan_result = scan_result;
            const MSG_LEN : usize = i2c_scan::SCAN_RESULT_STRING_LENGTH;
            let mut msg = String::<MSG_LEN>::new();
            match scan_result.format(&mut msg) {
                Ok(()) => info!("I2C scan result:\n{}", msg),
                Err(()) => info!("I2C scan result: too long for our buffer!"),
            }
        }

        Timer::after(Duration::from_secs(1)).await;
    }
}

#[embassy_executor::task]
async fn beeper_task(pwm_channel: embassy_rp::peripherals::PWM_CH3, beeper_pin: embassy_rp::peripherals::PIN_6) {
    let mut c: pwm::Config = Default::default();
    c.top = 0x8000;
    c.compare_a = 8;
    c.divider = fixed::FixedU16::from_num(20);
    let mut pwm = Pwm::new_output_a(pwm_channel, beeper_pin, c.clone());

    let mut toggle = false;
    loop {
        info!("PWM: duty={}/32768, divider={}", c.compare_a, c.divider.to_bits());
        Timer::after(Duration::from_millis(200)).await;
        //c.compare_a = c.compare_a.rotate_left(4);
        c.compare_a = if toggle { c.top/2 } else { 0 };
        //toggle = !toggle;
        c.divider -= fixed::FixedU16::from_num(0.1);
        if c.divider < 1 {
            c.divider = fixed::FixedU16::from_num(20);
        }
        toggle = true;
        pwm.set_config(&c);
    }
}

#[embassy_executor::task]
async fn uart_task(this: RS485<ModbusServer<ModBusRegs<'static>>>) {
    this.run_task().await;
}

// Zero offset for current measurement will be exponential smoothing with alpha=1/ZERO_OFFSET_FACTOR.
// The value in zero_offset_raw will be the smoothed offset times ZERO_OFFSET_FACTOR. This factor
// should be a power of two because we will divide by it.
const ZERO_OFFSET_FACTOR : u32 = 32;

struct AdcCurrentData {
    // Value measured while both MOSFETs are off
    // (multiplied by ZERO_OFFSET_FACTOR)
    zero_offset_raw: AtomicU32,
    // Current measured with 2k resistor (raw value and 1/10 mA)
    current_2k_raw: AtomicU16,
    current_2k_dezi_milliamps: AtomicU16,
    // Current measured while main MOSFET is/was on (raw value and 1/10 mA and when this was measured)
    current_on_raw: AtomicU16,
    current_on_dezi_milliamps: AtomicU16,
    current_on_time: Mutex<CriticalSectionRawMutex, Instant>,
}

impl AdcCurrentData {
    const fn const_default() -> AdcCurrentData {
        AdcCurrentData {
            zero_offset_raw: AtomicU32::new(0),
            current_2k_raw: AtomicU16::new(0),
            current_2k_dezi_milliamps: AtomicU16::new(0),
            current_on_raw: AtomicU16::new(0),
            current_on_dezi_milliamps: AtomicU16::new(0),
            current_on_time: Mutex::new(Instant::from_ticks(0)),
        }
    }
}

struct AdcData {
    analog_in1_raw: AtomicU16,
    analog_in1_millivolt: AtomicU16,
    vcc_raw: AtomicU16,
    vcc: AtomicU16,
    temp_raw: AtomicU16,
    temp_centicelsius: AtomicU16,

    currents: [AdcCurrentData; 2],
}

impl AdcData {
    const fn const_default() -> AdcData {
        AdcData {
            analog_in1_raw: AtomicU16::new(0),
            analog_in1_millivolt: AtomicU16::new(0),
            vcc_raw: AtomicU16::new(0),
            vcc: AtomicU16::new(0),
            temp_raw: AtomicU16::new(0),
            temp_centicelsius: AtomicU16::new(0),
            currents: [AdcCurrentData::const_default(), AdcCurrentData::const_default()],
        }
    }
}

#[embassy_executor::task]
async fn adc_task(shared_data: &'static AdcData, adc: ADC, mut en_measure_current: Output<'static, PIN_3>,
    mut analog_in1: PIN_26, mut current2: PIN_27, mut current1: PIN_28, mut measure_vcc: PIN_29, outputs_active: &'static AtomicU8) {
    let irq = interrupt::take!(ADC_IRQ_FIFO);
    let mut adc = Adc::new(adc, irq, adc::Config::default());

    let debug = true;
    let mut en_measure_current_toggle = 0;

    loop {
        if true {
            let level = adc.read(&mut analog_in1).await;
            // 3.05 V for 4096 counts, voltage divider with (10k + 5.1k) over 5.1k, result in mV:
            // level * 3.05/4096. * (10+5.1+5.1)/5.1 * 1000
            // -> level * 305 * (100+51+51) * 1000 / 100 / 4096 / 51
            // -> level * 305 * ((100+51+51)/2) * (1000/100) / 2048 / 51  --> fits in 32 bits for level=4096 (but barely)
            let value = level as u32 * 305 * ((100+51+51)/2) * (1000/100);
            let value = (value + 2048*51/2) / 2048 / 51;
            let value = if value > u16::MAX as u32 { u16::MAX } else { value as u16 };
            shared_data.analog_in1_raw.store(level, Ordering::Relaxed);
            shared_data.analog_in1_millivolt.store(value, Ordering::Relaxed);
            if debug {
                let value2 = 3.05*level as f32/4096. * (10.+2.*5.1)/5.1;
                info!("ADC analog_in1: {} cnt -> {} V ({} mV)", level, value2, value);
            }
        }

        if true {
            let level = adc.read(&mut measure_vcc).await;
            // 3.05V for 4096 counts, voltage divider with 100k over 10, result in mV:
            // level * 3.05/4096. * (100 + 10)/10 * 1000
            // -> level * 305 * 11 * 1000 / 100 / 4096
            let value = (level as u32 * 305 * 11 * 1000 / 100 + 2048) / 4096;
            let value = if value > u16::MAX as u32 { u16::MAX } else { value as u16 };
            shared_data.vcc_raw.store(level, Ordering::Relaxed);
            shared_data.vcc.store(value, Ordering::Relaxed);
            if debug {
                let vcc = 3.05 * level as f32 / 4096. * (100. + 10.)/10.;
                info!("ADC measure_vcc: {} cnt -> {} V ({} mV)", level, vcc, value);
            }
        }

        let outputs_were_active = outputs_active.load(Ordering::SeqCst);
        let mut measure_currents = true;
        if outputs_were_active != 0 && false {
            // output is active but also en_measure_current -> turn it off
            // -> Actually, don't do that because there is no harm and it can be useful for the other channel.
            if en_measure_current.is_set_high() {
                en_measure_current.set_low();
                measure_currents = false;
            }
            en_measure_current_toggle = 0;
        } else {
            match en_measure_current_toggle {
                0 | 8 => {
                    en_measure_current.set_level(if en_measure_current_toggle >= 8 { Level::High } else { Level::Low });
                    // skip in this loop to give it time to settle
                    measure_currents = false;
                }
                _ => {}
            }
            en_measure_current_toggle = (en_measure_current_toggle + 1) % 16;
        }

        // read another value between looking at output_active and measuring the currents
        if true {
            let level = adc.read_temperature().await;
            // According to chapter 4.9.5. Temperature Sensor in RP2040 datasheet
            let adc_vcc = 3.0522;  // from CJ431
            let celsius = 27.0 - (level as f32 * adc_vcc / 4096.0 - 0.706) / 0.001721;
            let value = celsius * 100.;
            let value = if value > u16::MAX as f32 { u16::MAX } else { value as u16 };
            shared_data.temp_raw.store(level, Ordering::Relaxed);
            shared_data.temp_centicelsius.store(value, Ordering::Relaxed);
            if debug {
                info!("Temp: {} -> {} deg C", level, celsius);
            }
        }

        if measure_currents {
            let levels = [
                adc.read(&mut current1).await,
                adc.read(&mut current2).await,
            ];
            let outputs_are_active = outputs_active.load(Ordering::SeqCst);
            //let en_measure_current_is_active = en_measure_current.is_set_high();  //FIXME I think is_set_high() has a bug.
            let en_measure_current_is_active = en_measure_current_toggle >= 8;
            for i in 0..2 {
                // 3.05 V for 4096 counts, shunt resistor is 0.1 ohms (i.e. 0.1 V/A), amplifier gain is 56, result should be mA/10
                // (level - offset) * 3.05/4096 / 0.1 * 1/56 * 1e4
                // -> (level - offset) * 305 * 10 * 1e4 / 56 / 4096 / 100
                // -> (level - offset) * 305 * 1000 / 56 / 4096
                // -> (level - offset) * 305 * (1000/8) / 4096 / 7
                let level = levels[i];
                let offset = (shared_data.currents[i].zero_offset_raw.load(Ordering::Relaxed)/ZERO_OFFSET_FACTOR) as u16;
                let level2 = if level > offset { level - offset } else { 0 };
                //info!("CUR{}: raw: {}, {}, zero={}", i, level, level2, shared_data.currents[i].zero_offset_raw.load(Ordering::Relaxed));
                let value = (level2 as u32 * 305 * (1000/8) + 7*4096/2) / 4096 / 7;
                let value = if value > u16::MAX as u32 { u16::MAX } else { value as u16 };

                let output_was_active = (outputs_were_active>>i) & 1 != 0;
                let output_is_active = (outputs_are_active>>i) & 1 != 0;
                #[allow(unused_variables, unused_assignments)]
                let mode : char;
                match (output_was_active, output_is_active, en_measure_current_is_active) {
                    (true, true, false) => {
                        // output was consistently (hopefully) turned on during our measurement
                        // and en_measure_current is off -> good measurement for current in "on" state
                        shared_data.currents[i].current_on_raw.store(levels[i], Ordering::Relaxed);
                        shared_data.currents[i].current_on_dezi_milliamps.store(value, Ordering::Relaxed);
                        *shared_data.currents[i].current_on_time.lock().await = Instant::now();
                        mode = 'O';
                    }
                    (false, false, false) => {
                        // output and en_measure_current are off -> good measurement for zero level

                        // fetch_update is exactly what we want but it doesn't seem to be available...
                        //shared_data.currents[i].zero_offset_raw.fetch_update(Ordering::Relaxed, Ordering::Relaxed,
                        //    |x| { x*(ZERO_OFFSET_FACTOR-1)/ZERO_OFFSET_FACTOR + levels[i] });
                        //SAFETY: We are the only writers for zero_offset_raw.
                        let x = shared_data.currents[i].zero_offset_raw.load(Ordering::Relaxed);
                        let x2 = x*(ZERO_OFFSET_FACTOR-1)/ZERO_OFFSET_FACTOR + level as u32;
                        shared_data.currents[i].zero_offset_raw.store(x2, Ordering::Relaxed);

                        mode = 'z';
                    }
                    (false, false, true) => {
                        // output is off and en_measure_current is on -> good measurement through 2k resistor
                        shared_data.currents[i].current_2k_raw.store(levels[i], Ordering::Relaxed);
                        shared_data.currents[i].current_2k_dezi_milliamps.store(value, Ordering::Relaxed);
                        mode = 'k';
                    }
                    _ => {
                        // inconsistent state of MOSFETs -> ignore this measurement
                        mode = '!';
                    }
                }
                
                if debug {
                    info!("ADC current{}: {}: {} -> {} [10*mA]", i, mode, level, value);
                }
            }

            //FIXME remove
            info!("CUR: 2k={}, {}, {}, zero={}, {} -> {}, {}",
                en_measure_current_is_active, levels[0], levels[1],
                shared_data.currents[0].zero_offset_raw.load(Ordering::Relaxed),
                shared_data.currents[1].zero_offset_raw.load(Ordering::Relaxed),
                shared_data.currents[0].current_2k_raw.load(Ordering::Relaxed),
                shared_data.currents[1].current_2k_raw.load(Ordering::Relaxed),
            );
        }

        if debug {
            Timer::after(Duration::from_secs(1)).await;
        } else {
            Timer::after(Duration::from_millis(1)).await;
        }
    }
}


#[derive(Clone, Copy, PartialEq, Eq)]
enum ReadType {
    HoldingRegister,
    InputRegister,
}

struct ModBusRegs<'a> {
    led_g: Output<'a, PIN_5>,
    button_boot2: Input<'a, PIN_11>,
    reed3: Input<'a, PIN_19>,
    reed4: Input<'a, PIN_20>,
    reed2: Input<'a, PIN_21>,
    reed1: Input<'a, PIN_22>,
    adc_data: &'a AdcData,

    consistent_read_type: ReadType,
    consistent_read_addr: u16,
    consistent_read_length: u16,
    consistent_read_data: [u16; 4],
}

impl<'a> ModBusRegs<'a> {
    fn read_reg_u64(self: &mut Self, read_type: ReadType, base_addr: u16, addr: u16, value: u64) -> Result<u16, ModbusErrorCode> {
        defmt::assert!(addr >= base_addr);
        defmt::assert!(addr < base_addr + 64/16);

        self.consistent_read_type = read_type;
        self.consistent_read_addr = base_addr;
        self.consistent_read_length = 64/16;
        self.consistent_read_data = [
            ((value >> 0) & 0xffff) as u16,
            ((value >> 16) & 0xffff) as u16,
            ((value >> 32) & 0xffff) as u16,
            ((value >> 48) & 0xffff) as u16,
        ];

        Ok(self.consistent_read_data[(addr - base_addr) as usize])
    }
}

impl<'a> ModbusRegisters for ModBusRegs<'a> {
    fn read_discrete_input(self: &mut Self, addr: u16) -> Result<bool, ModbusErrorCode> {
        match addr {
            0 => Ok(self.reed1.is_high()),
            1 => Ok(self.reed2.is_high()),
            2 => Ok(self.reed3.is_high()),
            3 => Ok(self.reed4.is_high()),
            4 => Ok(self.button_boot2.is_low()),
            _ => Err(ModbusErrorCode::IllegalDataAddress),
        }
    }

    fn read_holding_register(self: &mut Self, addr: u16) -> Result<u16, ModbusErrorCode> {
        if self.consistent_read_type == ReadType::HoldingRegister
                && addr >= self.consistent_read_addr && addr < self.consistent_read_addr + self.consistent_read_length {
            return Ok(self.consistent_read_data[(addr - self.consistent_read_addr) as usize]);
        }

        if addr == 1 {
            return Ok(42)
        }
        Err(ModbusErrorCode::IllegalDataAddress)
    }

    fn read_input_register(self: &mut Self, addr: u16) -> Result<u16, ModbusErrorCode> {
        if self.consistent_read_type == ReadType::InputRegister
                && addr >= self.consistent_read_addr && addr < self.consistent_read_addr + self.consistent_read_length {
            return Ok(self.consistent_read_data[(addr - self.consistent_read_addr) as usize]);
        }

        match addr {
            0 => Ok(42),

            1 => Ok(self.adc_data.analog_in1_raw.load(Ordering::Relaxed)),
            2 => Ok(self.adc_data.analog_in1_millivolt.load(Ordering::Relaxed)),
            3 => Ok(self.adc_data.vcc_raw.load(Ordering::Relaxed)),
            4 => Ok(self.adc_data.vcc.load(Ordering::Relaxed)),
            5 => Ok(self.adc_data.temp_raw.load(Ordering::Relaxed)),
            6 => Ok(self.adc_data.temp_centicelsius.load(Ordering::Relaxed)),

            7 => Ok((self.adc_data.currents[0].zero_offset_raw.load(Ordering::Relaxed) / ZERO_OFFSET_FACTOR) as u16),
            8 => Ok(self.adc_data.currents[0].current_2k_raw.load(Ordering::Relaxed)),
            9 => Ok(self.adc_data.currents[0].current_2k_dezi_milliamps.load(Ordering::Relaxed)),
            10 => Ok(self.adc_data.currents[0].current_on_raw.load(Ordering::Relaxed)),
            11 => Ok(self.adc_data.currents[0].current_on_dezi_milliamps.load(Ordering::Relaxed)),
            12 | 13 | 14 | 15 => self.read_reg_u64(ReadType::InputRegister, 12, addr,
                self.adc_data.currents[0].current_on_time.try_lock().map(
                    |x| x.as_micros()).unwrap_or(0)),

            16 => Ok((self.adc_data.currents[1].zero_offset_raw.load(Ordering::Relaxed) / ZERO_OFFSET_FACTOR) as u16),
            17 => Ok(self.adc_data.currents[1].current_2k_raw.load(Ordering::Relaxed)),
            18 => Ok(self.adc_data.currents[1].current_2k_dezi_milliamps.load(Ordering::Relaxed)),
            19 => Ok(self.adc_data.currents[1].current_on_raw.load(Ordering::Relaxed)),
            20 => Ok(self.adc_data.currents[1].current_on_dezi_milliamps.load(Ordering::Relaxed)),
            21 | 22 | 23 | 24 => self.read_reg_u64(ReadType::InputRegister, 21, addr,
                self.adc_data.currents[1].current_on_time.try_lock().map(
                    |x| x.as_micros()).unwrap_or(0)),

            _ => Err(ModbusErrorCode::IllegalDataAddress)
        }
    }

    fn write_coil(self: &mut Self, addr: u16, value: bool) -> Result<(), ModbusErrorCode> {
        match addr {
            0 => { self.led_g.set_level(Level::from(value)); Ok(()) },
            _ => Err(ModbusErrorCode::IllegalDataAddress),
        }
    }

    fn write_register(self: &mut Self, addr: u16, value: u16) -> Result<u16, ModbusErrorCode> {
        Err(ModbusErrorCode::IllegalDataAddress)
    }
}

#[embassy_executor::main]
async fn main(spawner: Spawner) {
    let p = embassy_rp::init(Default::default());
    info!("starting");
    // pinout:
    let mut _drive2 = Output::new(p.PIN_0, Level::Low);
    let mut _drive1 = Output::new(p.PIN_1, Level::Low);
    //let LED_W = p.PIN_2;
    let _ws2812_display = p.PIN_2;
    //let LED_Y = p.PIN_3;
    let en_measure_current = Output::new(p.PIN_3, Level::Low);
    let mut led_b = Output::new(p.PIN_4, Level::Low);
    let led_g = Output::new(p.PIN_5, Level::Low);
    let led_r = p.PIN_6;
    let _matrix_in1 = Input::new(p.PIN_7, Pull::Up);
    let _sbu1 = p.PIN_8;
    let _sbu2 = p.PIN_9;
    let _vbus_det = p.PIN_10;
    let button_boot2 = Input::new(p.PIN_11, Pull::Up);
    let sda = p.PIN_12;
    let scl = p.PIN_13;
    let _ws2811_red_in = Input::new(p.PIN_14, Pull::None);
    let tx_en = p.PIN_15;
    let tx = p.PIN_16;
    let rx = p.PIN_17;
    let _matrix_in2 = Input::new(p.PIN_18, Pull::Up);
    let reed3 = Input::new(p.PIN_19, Pull::Up);
    let reed4 = Input::new(p.PIN_20, Pull::Up);
    let reed2 = Input::new(p.PIN_21, Pull::Up);
    let reed1 = Input::new(p.PIN_22, Pull::Up);
    let _matrix_in3 = Input::new(p.PIN_23, Pull::Up);
    let _digout1 = p.PIN_24;
    let _digout2 = p.PIN_25;
    let analog_in1 = p.PIN_26;
    let current2 = p.PIN_27;
    let current1 = p.PIN_28;
    let measure_vcc = p.PIN_29;

    let i2c_irq = interrupt::take!(I2C0_IRQ);
    let mut i2c_config = i2c::Config::default();
    i2c_config.frequency = 400_000;
    unwrap!(spawner.spawn(i2c_task(p.I2C0, scl, sda, i2c_irq, i2c_config)));

    static ADC_DATA: AdcData = AdcData::const_default();
    static OUTPUTS_ACTIVE: AtomicU8 = AtomicU8::new(0);
    unwrap!(spawner.spawn(adc_task(&ADC_DATA, p.ADC, en_measure_current, analog_in1, current2, current1, measure_vcc, &OUTPUTS_ACTIVE)));

    // use 19200 baud in 8E1 mode - not great but it's the Modbus default
    let mut uart_config = uart::Config::default();
    uart_config.baudrate = 19200;
    uart_config.parity = Parity::ParityEven;
    let rs485 = RS485::new(
        p.UART0, rx, tx, tx_en, interrupt::take!(UART0_IRQ), p.DMA_CH1, uart_config,
        p.PIO0, p.DMA_CH0, p.DMA_CH2,
        ModbusServer::new(ModBusRegs {
            led_g,
            button_boot2,
            reed1, reed2, reed3, reed4,
            adc_data: &ADC_DATA,
            consistent_read_type: ReadType::InputRegister,
            consistent_read_addr: u16::default(),
            consistent_read_length: u16::default(),
            consistent_read_data: [0; 4],
        }),
    );
    unwrap!(spawner.spawn(uart_task(rs485)));

    if false {
        unwrap!(spawner.spawn(beeper_task(p.PWM_CH3, led_r)));
    }

    loop {
        led_b.set_high();
        Timer::after(Duration::from_secs(1)).await;

        led_b.set_low();
        Timer::after(Duration::from_secs(1)).await;
    }
}