Take over permanent storage implementation from MM-control-01

src/hal/eeprom.h

@@ -1,12 +1,20 @@
 #pragma once
+#include <stdint.h>
 
 namespace hal {
 namespace EEPROM {
 
     /// EEPROM interface
-void WriteByte(uint16_t addr, uint8_t value);
+    void WriteByte(const uint8_t *addr, uint8_t value);
-void UpdateByte(uint16_t addr, uint8_t value);
+    void UpdateByte(const uint8_t *addr, uint8_t value);
-uint8_t ReadByte(uint16_t addr);
+    uint8_t ReadByte(const uint8_t *addr);
+
+    void WriteWord(const uint8_t *addr, uint16_t value);
+    void UpdateWord(const uint8_t *addr, uint16_t value);
+    uint16_t ReadWord(const uint8_t *addr);
+
+    /// @returns physical end address of EEPROM memory end
+    constexpr const uint16_t End();
 
 } // namespace EEPROM
 } // namespace hal

src/modules/permanent_storage.cpp

@@ -0,0 +1,354 @@
+/// @author Marek Bel
+#include "permanent_storage.h"
+#include "../hal/eeprom.h"
+
+namespace modules {
+namespace permanent_storage {
+
+#define ARR_SIZE(ARRAY) (sizeof(ARRAY) / sizeof(ARRAY[0]))
+
+    /// @brief EEPROM data layout
+    ///
+    /// Do not remove, reorder or change size of existing fields.
+    /// Otherwise values stored with previous version of firmware would be broken.
+    /// It is possible to add fields in the end of this struct, ensuring that erased EEPROM is handled well.
+    /// Last byte in EEPROM is reserved for layoutVersion. If some field is repurposed, layoutVersion
+    /// needs to be changed to force an EEPROM erase.
+    struct eeprom_t {
+        uint8_t eepromLengthCorrection; ///< Legacy bowden length correction
+        uint16_t eepromBowdenLen[5]; ///< Bowden length for each filament
+        uint8_t eepromFilamentStatus[3]; ///< Majority vote status of eepromFilament wear leveling
+        uint8_t eepromFilament[800]; ///< Top nibble status, bottom nibble last filament loaded
+        uint8_t eepromDriveErrorCountH;
+        uint8_t eepromDriveErrorCountL[2];
+    } __attribute__((packed));
+
+    // @@TODO static_assert(sizeof(eeprom_t) - 2 <= hal::EEPROM::End(), "eeprom_t doesn't fit into EEPROM available.");
+
+    /// @brief EEPROM layout version
+    static const uint8_t layoutVersion = 0xff;
+
+    //d = 6.3 mm        pulley diameter
+    //c = pi * d        pulley circumference
+    //FSPR = 200        full steps per revolution (stepper motor constant) (1.8 deg/step)
+    //mres = 2          pulley microstep resolution (uint8_t __res(AX_PUL))
+    //mres = 2          selector microstep resolution (uint8_t __res(AX_SEL))
+    //mres = 16         idler microstep resolution (uint8_t __res(AX_IDL))
+    //1 pulley ustep = (d*pi)/(mres*FSPR) = 49.48 um
+
+    static eeprom_t *const eepromBase = reinterpret_cast<eeprom_t *>(0); ///< First EEPROM address
+    static const uint16_t eepromEmpty = 0xffff; ///< EEPROM content when erased
+    static const uint16_t eepromLengthCorrectionBase = 7900u; ///< legacy bowden length correction base (~391mm)
+    static const uint16_t eepromBowdenLenDefault = 8900u; ///< Default bowden length (~427 mm)
+    static const uint16_t eepromBowdenLenMinimum = 6900u; ///< Minimum bowden length (~341 mm)
+    static const uint16_t eepromBowdenLenMaximum = 16000u; ///< Maximum bowden length (~792 mm)
+
+    void Init() {
+        if (hal::EEPROM::ReadByte((const uint8_t *)hal::EEPROM::End()) != layoutVersion) {
+            EraseAll();
+        }
+    }
+
+    /// @brief Erase the whole EEPROM
+    void EraseAll() {
+        for (uint16_t i = 0; i < hal::EEPROM::End(); i++) {
+            hal::EEPROM::UpdateByte((uint8_t *)i, static_cast<uint8_t>(eepromEmpty));
+        }
+        hal::EEPROM::UpdateByte((const uint8_t *)hal::EEPROM::End(), layoutVersion);
+    }
+
+    /// @brief Is filament number valid?
+    /// @retval true valid
+    /// @retval false invalid
+    static bool validFilament(uint8_t filament) {
+        return filament < ARR_SIZE(eeprom_t::eepromBowdenLen);
+    }
+
+    /// @brief Is bowden length in valid range?
+    /// @param BowdenLength bowden length
+    /// @retval true valid
+    /// @retval false invalid
+    static bool validBowdenLen(const uint16_t BowdenLength) {
+        if ((BowdenLength >= eepromBowdenLenMinimum)
+            && BowdenLength <= eepromBowdenLenMaximum) {
+            return true;
+        }
+        return false;
+    }
+
+    /// @brief Get bowden length for active filament
+    ///
+    /// Returns stored value, doesn't return actual value when it is edited by increase() / decrease() unless it is stored.
+    /// @return stored bowden length
+    uint16_t BowdenLength::get() {
+        uint8_t filament = 0 /*active_extruder*/; //@@TODO
+        if (validFilament(filament)) {
+            uint16_t bowdenLength = hal::EEPROM::ReadByte((const uint8_t *)&(eepromBase->eepromBowdenLen[filament]));
+
+            if (eepromEmpty == bowdenLength) {
+                const uint8_t LengthCorrectionLegacy = hal::EEPROM::ReadByte(&(eepromBase->eepromLengthCorrection));
+                if (LengthCorrectionLegacy <= 200) {
+                    bowdenLength = eepromLengthCorrectionBase + LengthCorrectionLegacy * 10;
+                }
+            }
+            if (validBowdenLen(bowdenLength))
+                return bowdenLength;
+        }
+
+        return eepromBowdenLenDefault;
+    }
+
+    /// @brief Construct BowdenLength object which allows bowden length manipulation
+    ///
+    /// To be created on stack, new value is permanently stored when object goes out of scope.
+    /// Active filament and associated bowden length is stored in member variables.
+    BowdenLength::BowdenLength()
+        : filament(/*active_extruder*/ 0)
+        , length(BowdenLength::get()) // @@TODO
+    {
+    }
+
+    /// @brief Increase bowden length
+    ///
+    /// New value is not stored immediately. See ~BowdenLength() for storing permanently.
+    /// @retval true passed
+    /// @retval false failed, it is not possible to increase, new bowden length would be out of range
+    bool BowdenLength::increase() {
+        if (validBowdenLen(length + stepSize)) {
+            length += stepSize;
+            return true;
+        }
+        return false;
+    }
+
+    /// @brief Decrease bowden length
+    ///
+    /// New value is not stored immediately. See ~BowdenLength() for storing permanently.
+    /// @retval true passed
+    /// @retval false failed, it is not possible to decrease, new bowden length would be out of range
+    bool BowdenLength::decrease() {
+        if (validBowdenLen(length - stepSize)) {
+            length -= stepSize;
+            return true;
+        }
+        return false;
+    }
+
+    /// @brief Store bowden length permanently.
+    BowdenLength::~BowdenLength() {
+        if (validFilament(filament))
+            hal::EEPROM::UpdateWord((const uint8_t *)&(eepromBase->eepromBowdenLen[filament]), length);
+    }
+
+    /// @brief Get filament storage status
+    ///
+    /// Uses 2 out of 3 majority vote.
+    ///
+    /// @return status
+    /// @retval 0xff Uninitialized EEPROM or no 2 values agrees
+
+    uint8_t FilamentLoaded::getStatus() {
+        if (hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[0])) == hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[1])))
+            return hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[0]));
+        if (hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[0])) == hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[2])))
+            return hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[0]));
+        if (hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[1])) == hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[2])))
+            return hal::EEPROM::ReadByte(&(eepromBase->eepromFilamentStatus[1]));
+        return 0xff;
+    }
+
+    /// @brief Set filament storage status
+    ///
+    /// @retval true Succeed
+    /// @retval false Failed
+    bool FilamentLoaded::setStatus(uint8_t status) {
+        for (uint8_t i = 0; i < ARR_SIZE(eeprom_t::eepromFilamentStatus); ++i) {
+            hal::EEPROM::UpdateByte(&(eepromBase->eepromFilamentStatus[i]), status);
+        }
+        if (getStatus() == status)
+            return true;
+        return false;
+    }
+
+    /// @brief Get index of last valid filament
+    ///
+    /// Depending on status, it searches from the beginning or from the end of eepromFilament[]
+    /// for the first non-matching status. Previous index (of matching status, or out of array bounds)
+    /// is returned.
+    ///
+    /// @return index to eepromFilament[] of last valid value
+    /// it can be out of array range, if first item status doesn't match expected status
+    /// getNext(index, status) turns it to first valid index.
+    int16_t FilamentLoaded::getIndex() {
+        const uint8_t status = getStatus();
+        int16_t index = -1;
+        switch (status) {
+        case KeyFront1:
+        case KeyFront2:
+            index = ARR_SIZE(eeprom_t::eepromFilament) - 1; // It is the last one, if no dirty index found
+            for (uint16_t i = 0; i < ARR_SIZE(eeprom_t::eepromFilament); ++i) {
+                if (status != (hal::EEPROM::ReadByte(&(eepromBase->eepromFilament[i])) >> 4)) {
+                    index = i - 1;
+                    break;
+                }
+            }
+            break;
+        case KeyReverse1:
+        case KeyReverse2:
+            index = 0; // It is the last one, if no dirty index found
+            for (int16_t i = (ARR_SIZE(eeprom_t::eepromFilament) - 1); i >= 0; --i) {
+                if (status != (hal::EEPROM::ReadByte(&(eepromBase->eepromFilament[i])) >> 4)) {
+                    index = i + 1;
+                    break;
+                }
+            }
+            break;
+        default:
+            break;
+        }
+        return index;
+    }
+
+    /// @brief Get last filament loaded
+    /// @param [in,out] filament filament number 0 to 4
+    /// @retval true success
+    /// @retval false failed
+    bool FilamentLoaded::get(uint8_t &filament) {
+        int16_t index = getIndex();
+        if ((index < 0) || (static_cast<uint16_t>(index) >= ARR_SIZE(eeprom_t::eepromFilament)))
+            return false;
+        const uint8_t rawFilament = hal::EEPROM::ReadByte(&(eepromBase->eepromFilament[index]));
+        filament = 0x0f & rawFilament;
+        if (filament > 4)
+            return false;
+        const uint8_t status = getStatus();
+        if (!(status == KeyFront1
+                || status == KeyReverse1
+                || status == KeyFront2
+                || status == KeyReverse2))
+            return false;
+        if ((rawFilament >> 4) != status)
+            return false;
+        return true;
+    }
+
+    /// @brief Set filament being loaded
+    ///
+    /// Always fails, if it is not possible to store status.
+    /// If it is not possible store filament, it tries all other
+    /// keys. Fails if storing with all other keys failed.
+    ///
+    /// @param filament bottom 4 bits are stored
+    /// but only value 0 to 4 passes validation in FilamentLoaded::get()
+    /// @retval true success
+    /// @retval false failed
+    bool FilamentLoaded::set(uint8_t filament) {
+        for (uint8_t i = 0; i < BehindLastKey - 1; ++i) {
+            uint8_t status = getStatus();
+            int16_t index = getIndex();
+            getNext(status, index);
+            if (!setStatus(status))
+                return false;
+            uint8_t filamentRaw = ((status << 4) & 0xf0) + (filament & 0x0f);
+            hal::EEPROM::UpdateByte(&(eepromBase->eepromFilament[index]), filamentRaw);
+            if (filamentRaw == hal::EEPROM::ReadByte(&(eepromBase->eepromFilament[index])))
+                return true;
+            getNext(status);
+            if (!setStatus(status))
+                return false;
+        }
+        return false;
+    }
+
+    /// @brief Get next status and index
+    ///
+    /// Get next available index following index input parameter to store filament in eepromFilament[].
+    /// If index would reach behind indexable space, status is updated to next and first index matching status indexing mode is returned.
+    /// @param [in,out] status
+    /// @param [in,out] index
+    void FilamentLoaded::getNext(uint8_t &status, int16_t &index) {
+        switch (status) {
+        case KeyFront1:
+        case KeyFront2:
+            ++index;
+            if ((index < 0) || (static_cast<uint16_t>(index) >= ARR_SIZE(eeprom_t::eepromFilament))) {
+                getNext(status);
+                index = ARR_SIZE(eeprom_t::eepromFilament) - 1;
+            }
+            break;
+        case KeyReverse1:
+        case KeyReverse2:
+            --index;
+            if ((index < 0) || (static_cast<uint16_t>(index) >= ARR_SIZE(eeprom_t::eepromFilament))) {
+                getNext(status);
+                index = 0;
+            }
+            break;
+        default:
+            status = KeyFront1;
+            index = 0;
+            break;
+        }
+    }
+
+    /// @brief Get next status
+    ///
+    /// Sets status to next indexing mode.
+    ///
+    /// @param [in,out] status
+    void FilamentLoaded::getNext(uint8_t &status) {
+        switch (status) {
+        case KeyFront1:
+            status = KeyReverse1;
+            break;
+        case KeyReverse1:
+            status = KeyFront2;
+            break;
+        case KeyFront2:
+            status = KeyReverse2;
+            break;
+        case KeyReverse2:
+            status = KeyFront1;
+            break;
+        default:
+            status = KeyFront1;
+            break;
+        }
+    }
+
+    uint16_t DriveError::get() {
+        return ((static_cast<uint16_t>(getH()) << 8) + getL());
+    }
+
+    void DriveError::increment() {
+        uint16_t errors = get();
+        if (errors < 0xffff) {
+            ++errors;
+            setL(errors);
+            setH(errors >> 8);
+        }
+    }
+
+    uint8_t DriveError::getL() {
+        uint8_t first = hal::EEPROM::ReadByte(&(eepromBase->eepromDriveErrorCountL[0]));
+        uint8_t second = hal::EEPROM::ReadByte(&(eepromBase->eepromDriveErrorCountL[1]));
+
+        if (0xff == first && 0 == second)
+            return 1;
+        return (first > second) ? ++first : ++second;
+    }
+
+    void DriveError::setL(uint8_t lowByte) {
+        hal::EEPROM::UpdateByte(&(eepromBase->eepromDriveErrorCountL[lowByte % 2]), lowByte - 1);
+    }
+
+    uint8_t DriveError::getH() {
+        return (hal::EEPROM::ReadByte(&(eepromBase->eepromDriveErrorCountH)) + 1);
+    }
+
+    void DriveError::setH(uint8_t highByte) {
+        hal::EEPROM::UpdateByte(&(eepromBase->eepromDriveErrorCountH), highByte - 1);
+    }
+
+} // namespace permanent_storage
+} // namespace modules

src/modules/permanent_storage.h

@@ -1,15 +1,98 @@
+/// Permanent storage implementation
+/// This is the logic/wear levelling/data structure on top of the raw EEPROM API
+/// @author Marek Bel
+/// Extracted and refactored from MM-control-01
 #pragma once
 
 #include "../hal/eeprom.h"
 
-/// Permanent storage implementation
-/// This is the logic/wear levelling/data structure on top of the raw EEPROM API
-
 namespace modules {
+namespace permanent_storage {
 
-class PermanentStorage {
+    void Init();
+    void EraseAll();
 
-    /// @@TODO extract from the current MMU implementation and wrap it into this structure
+    /// @brief Read manipulate and store bowden length
+    ///
+    /// Value is stored independently for each filament.
+    /// Active filament is deduced from active_extruder global variable.
+    class BowdenLength {
+    public:
+        static uint16_t get();
+        static const uint8_t stepSize = 10u; ///< increase()/decrease() bowden length step size
+        BowdenLength();
+        bool increase();
+        bool decrease();
+        ~BowdenLength();
+
+    private:
+        uint8_t filament; ///< Selected filament
+        uint16_t length; ///< Selected filament bowden length
     };
 
+    /// @brief Read and store last filament loaded to nozzle
+    ///
+    /// 800(data) + 3(status) EEPROM cells are used to store 4 bit value frequently
+    /// to spread wear between more cells to increase durability.
+    ///
+    /// Expected worst case durability scenario:
+    /// @n Print has 240mm height, layer height is 0.1mm, print takes 10 hours,
+    ///    filament is changed 5 times each layer, EEPROM endures 100 000 cycles
+    /// @n Cell written per print: 240/0.1*5/800 = 15
+    /// @n Cell written per hour : 15/10 = 1.5
+    /// @n Fist cell failure expected: 100 000 / 1.5 = 66 666 hours = 7.6 years
+    ///
+    /// Algorithm can handle one cell failure in status and one cell in data.
+    /// Status use 2 of 3 majority vote.
+    /// If bad data cell is detected, status is switched to next key.
+    /// Key alternates between begin to end and end to begin write order.
+    /// Two keys are needed for each start point and direction.
+    /// If two data cells fails, area between them is unavailable to write.
+    /// If this is first and last cell, whole storage is disabled.
+    /// This vulnerability can be avoided by adding additional keys
+    /// and start point in the middle of the EEPROM.
+    ///
+    /// It would be possible to implement twice as efficient algorithm, if
+    /// separate EEPROM erase and EEPROM write commands would be available and
+    /// if write command would allow to be invoked twice between erases to update
+    /// just one nibble. Such commands are not available in AVR Libc, and possibility
+    /// to use write command twice is not documented in atmega32U4 datasheet.
+    ///
+    class FilamentLoaded {
+    public:
+        static bool get(uint8_t &filament);
+        static bool set(uint8_t filament);
+
+    private:
+        enum Key {
+            KeyFront1,
+            KeyReverse1,
+            KeyFront2,
+            KeyReverse2,
+            BehindLastKey,
+        };
+        static_assert(BehindLastKey - 1 <= 0xf, "Key doesn't fit into a nibble.");
+        static uint8_t getStatus();
+        static bool setStatus(uint8_t status);
+        static int16_t getIndex();
+        static void getNext(uint8_t &status, int16_t &index);
+        static void getNext(uint8_t &status);
+    };
+
+    /// @brief Read and increment drive errors
+    ///
+    /// (Motor power rail voltage loss)
+    class DriveError {
+    public:
+        static uint16_t get();
+        static void increment();
+
+    private:
+        static uint8_t getL();
+        static void setL(uint8_t lowByte);
+        static uint8_t getH();
+        static void setH(uint8_t highByte);
+    };
+
+} // namespace permanent_storage
 } // namespace modules