try to fix submodule

firmware/lib/Arduino-FOC-drivers/src/encoders/stm32hwencoder/README.md

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+# SimpleFOC Driver for STM32 hardware encoder
+
+This encoder driver uses the STM32 timer hardware to track the A/B impulses, which is much more efficient (and will support higher speeds) than the generic interrupt-based solution used by the standard encoder driver.
+
+Big thank you to @conroy-cheers for originally contributing this code in pull request #114 to the simplefoc repository. Due its hardware-specific nature we moved the code to this drivers repository.
+
+## Warning
+
+This code has not been tested much! Use at your own risk, your milage may vary.
+I have tested on: STM32F401CC/TIM4-PB6,PB7
+
+## Hardware setup
+
+The ABI signals of your encoder will have to be connected to the STM32 MCU in such a way that all signals are connected to the same timer. Consult your STM32 chip's datasheet for more information on which pins connect to which timer.
+
+Not all of the timers support the encoder mode, so check the datasheet which timers can be used.
+
+An excellent option can be to use the STM32CubeIDE software's pin assignment view to quickly check which pins connect to which timer.
+
+Note that the index (I) pin is currently not used.
+
+
+## Software setup
+
+There is no need for interrupt functions or their configuration with this encoder class, so usage is quite simple:
+
+```c++
+#include "Arduino.h"
+#include "Wire.h"
+#include "SPI.h"
+#include "SimpleFOC.h"
+#include "SimpleFOCDrivers.h"
+#include "encoders/stm32hwencoder/STM32HWEncoder.h"
+
+
+#define ENCODER_PPR 500
+#define ENCODER_PIN_A PB6
+#define ENCODER_PIN_B PB7
+#define ENCODER_PIN_I PC13
+
+
+STM32HWEncoder encoder = STM32HWEncoder(ENCODER_PPR, ENCODER_PIN_A, ENCODER_PIN_B, ENCODER_PIN_I);
+
+
+void setup() {
+    encoder.init();
+}
+
+```

firmware/lib/Arduino-FOC-drivers/src/encoders/stm32hwencoder/STM32HWEncoder.cpp

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+#include "STM32HWEncoder.h"
+
+#if defined(_STM32_DEF_)
+
+/*
+  HardwareEncoder(int cpr)
+*/
+STM32HWEncoder::STM32HWEncoder(unsigned int _ppr, int8_t pinA, int8_t pinB, int8_t pinI) {
+    cpr = _ppr * 4; // 4x for quadrature
+    _pinA = digitalPinToPinName(pinA);
+    _pinB = digitalPinToPinName(pinB);
+    _pinI = digitalPinToPinName(pinI);
+}
+
+/*
+  Shaft angle calculation
+*/
+float STM32HWEncoder::getSensorAngle() { 
+    return _2PI * encoder_handle.Instance->CNT / static_cast<float>(cpr);
+}
+
+// getter for index pin
+int STM32HWEncoder::needsSearch() { return false; }
+
+// private function used to determine if encoder has index
+int STM32HWEncoder::hasIndex() { return 0; }
+
+// encoder initialisation of the hardware pins
+void STM32HWEncoder::init() {
+    // GPIO configuration
+    TIM_TypeDef *InstanceA = (TIM_TypeDef *)pinmap_peripheral(_pinA, PinMap_TIM);
+    TIM_TypeDef *InstanceB = (TIM_TypeDef *)pinmap_peripheral(_pinB, PinMap_TIM);
+    if (InstanceA != InstanceB) {
+        initialized = false;
+        return;
+    }
+    pinmap_pinout(_pinA, PinMap_TIM);
+    pinmap_pinout(_pinB, PinMap_TIM);
+
+    // set up timer for encoder
+    encoder_handle.Init.Period = cpr - 1;
+    encoder_handle.Init.Prescaler = 0;
+    encoder_handle.Init.ClockDivision = 0;
+    encoder_handle.Init.CounterMode = TIM_COUNTERMODE_UP;
+    encoder_handle.Init.RepetitionCounter = 0;
+    encoder_handle.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
+
+    TIM_Encoder_InitTypeDef encoder_config;
+
+    encoder_config.EncoderMode = TIM_ENCODERMODE_TI12;
+
+    encoder_config.IC1Polarity = TIM_ICPOLARITY_RISING;
+    encoder_config.IC1Selection = TIM_ICSELECTION_DIRECTTI;
+    encoder_config.IC1Prescaler = TIM_ICPSC_DIV1;
+    encoder_config.IC1Filter = 0;
+
+    encoder_config.IC2Polarity = TIM_ICPOLARITY_RISING;
+    encoder_config.IC2Selection = TIM_ICSELECTION_DIRECTTI;
+    encoder_config.IC2Prescaler = TIM_ICPSC_DIV1;
+    encoder_config.IC2Filter = 0;
+
+    encoder_handle.Instance = InstanceA; // e.g. TIM4;
+    enableTimerClock(&encoder_handle);
+
+    if (HAL_TIM_Encoder_Init(&encoder_handle, &encoder_config) != HAL_OK) {
+        initialized = false;
+        return;
+    }
+
+    if (HAL_TIM_Encoder_Start(&encoder_handle, TIM_CHANNEL_1) != HAL_OK) {
+        initialized = false;
+        return;
+    }
+
+    initialized = true;
+}
+
+#endif

firmware/lib/Arduino-FOC-drivers/src/encoders/stm32hwencoder/STM32HWEncoder.h

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+
+#pragma once
+
+#include <Arduino.h>
+
+
+#if defined(_STM32_DEF_)
+
+#include <HardwareTimer.h>
+#include "common/base_classes/Sensor.h"
+#include "common/foc_utils.h"
+
+class STM32HWEncoder : public Sensor {
+  public:
+    /**
+    Encoder class constructor
+    @param ppr  impulses per rotation  (cpr=ppr*4)
+    */
+    explicit STM32HWEncoder(unsigned int ppr, int8_t pinA, int8_t pinB, int8_t pinI=-1);
+
+    void init() override;
+    int needsSearch() override;
+    int hasIndex();  // !< function returning 1 if encoder has index pin and 0 if not.
+
+    bool initialized = false;
+    uint32_t cpr;  //!< encoder cpr number
+    PinName _pinA, _pinB, _pinI;
+    
+  protected:
+    float getSensorAngle() override;
+    
+    TIM_HandleTypeDef encoder_handle;
+
+};
+
+#endif