Add CAN

CMakeLists.txt

@@ -21,7 +21,7 @@ set(CMAKE_SHARED_LINKER_FLAGS "${COMMON_LINKER_FLAGS}")
 
 project(bobbycar-controller-firmware ASM C CXX)
 
-add_definitions(-DUSE_HAL_DRIVER -DSTM32F103xE)
+add_definitions(-DUSE_HAL_DRIVER -DSTM32F103xE -DFEATURE_CAN)
 
 include_directories(
     .
@@ -54,6 +54,7 @@ add_executable(firmware.elf
     STM32CubeF1/Drivers/STM32F1xx_HAL_Driver/Src/stm32f1xx_hal_adc.c
     STM32CubeF1/Drivers/STM32F1xx_HAL_Driver/Src/stm32f1xx_hal_uart.c
     STM32CubeF1/Drivers/STM32F1xx_HAL_Driver/Src/stm32f1xx_hal_dma.c
+    STM32CubeF1/Drivers/STM32F1xx_HAL_Driver/Src/stm32f1xx_hal_can.c
 
     bobbycar-foc-model/BLDC_controller.h
     bobbycar-foc-model/BLDC_controller.c
@@ -68,6 +69,8 @@ add_executable(firmware.elf
     config.h
     defines.h
     main.cpp
+    can.c
+    can_feedc0de.cpp
 )
 
 add_custom_command(OUTPUT firmware.hex

can.c

@@ -0,0 +1,369 @@
+#include "stm32f1xx_hal.h"
+
+#include "can_feedc0de.h"
+#include "can.h"
+
+/* Definition for CANx clock resources */
+#define CANx                           CAN1
+#define CANx_CLK_ENABLE()              __HAL_RCC_CAN1_CLK_ENABLE()
+#define CANx_GPIO_CLK_ENABLE()         __HAL_RCC_GPIOB_CLK_ENABLE()
+
+#define CANx_FORCE_RESET()             __HAL_RCC_CAN1_FORCE_RESET()
+#define CANx_RELEASE_RESET()           __HAL_RCC_CAN1_RELEASE_RESET()
+
+/* Definition for CANx Pins */
+#define CANx_TX_PIN                    GPIO_PIN_9
+#define CANx_TX_GPIO_PORT              GPIOB
+#define CANx_RX_PIN                    GPIO_PIN_8
+#define CANx_RX_GPIO_PORT              GPIOB
+
+/* Definition for CANx AFIO Remap */
+#define CANx_AFIO_REMAP_CLK_ENABLE()   __HAL_RCC_AFIO_CLK_ENABLE()
+#define CANx_AFIO_REMAP_RX_TX_PIN()    __HAL_AFIO_REMAP_CAN1_2()
+
+/* Definition for CAN's NVIC */
+#define CANx_RX_IRQn                   USB_LP_CAN1_RX0_IRQn
+#define CANx_RX_IRQHandler             USB_LP_CAN1_RX0_IRQHandler
+#define CANx_TX_IRQn                   USB_HP_CAN1_TX_IRQn
+#define CANx_TX_IRQHandler             USB_HP_CAN1_TX_IRQHandler
+
+
+/**
+  ******************************************************************************
+  * @file    CAN/CAN_Networking/Src/main.c
+  * @author  MCD Application Team
+  * @brief   This example shows how to configure the CAN peripheral
+  *          to send and receive CAN frames in normal mode. The sent frames
+  *          are used to control Leds by pressing KEY Push Button.
+  ******************************************************************************
+  * @attention
+  *
+  * <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
+  * All rights reserved.</center></h2>
+  *
+  * This software component is licensed by ST under BSD 3-Clause license,
+  * the "License"; You may not use this file except in compliance with the
+  * License. You may obtain a copy of the License at:
+  *                        opensource.org/licenses/BSD-3-Clause
+  *
+  ******************************************************************************
+  */
+
+/* Private variables ---------------------------------------------------------*/
+uint8_t ubKeyNumber = 0x0;
+CAN_HandleTypeDef     CanHandle;
+CAN_TxHeaderTypeDef   TxHeader;
+CAN_RxHeaderTypeDef   RxHeader;
+uint8_t               TxData[8];
+uint8_t               RxData[8];
+uint32_t              TxMailbox;
+
+/* Private function prototypes -----------------------------------------------*/
+static void __NO_RETURN Error_Handler(void);
+static void CAN_MspInit(CAN_HandleTypeDef *hcan);
+static void CAN_MspDeInit(CAN_HandleTypeDef *hcan);
+static void CAN_RxFifo0MsgPendingCallback(CAN_HandleTypeDef *hcan);
+static void CAN_TxMailboxCompleteCallback(CAN_HandleTypeDef *hcan);
+
+/* Private functions ---------------------------------------------------------*/
+
+static uint32_t len_to_dlc(uint8_t len)
+{
+  uint32_t len_u32 = len;
+
+  if (len_u32 <= 8)
+    return len_u32;
+
+  // CAN-FD-only lengths currently not supported
+  Error_Handler();
+}
+
+static uint8_t dlc_to_len(uint32_t dlc)
+{
+  // Check if DLC valid
+  if (dlc & ~0xFu)
+    Error_Handler();
+
+  // CAN-FD-only lengths currently not supported
+  if (dlc > 8)
+    Error_Handler();
+
+  return dlc;
+}
+
+/**
+  * @brief  Main program.
+  * @param  None
+  * @retval None
+  */
+void can_test(void)
+{
+  TxHeader.DLC = 2;
+  TxHeader.StdId = 0x321;
+
+  /* Set the data to be transmitted */
+  TxData[0] = ubKeyNumber + 1;
+  TxData[1] = 0xAD;
+
+  /* Start the Transmission process */
+  if (HAL_CAN_AddTxMessage(&CanHandle, &TxHeader, TxData, &TxMailbox) != HAL_OK)
+  {
+    /* Transmission request Error */
+    Error_Handler();
+  }
+}
+
+void can_tx(uint16_t id, const uint8_t* data, uint8_t len)
+{
+  TxHeader.StdId = id;
+  TxHeader.DLC = len_to_dlc(len);
+
+  while (HAL_CAN_GetTxMailboxesFreeLevel(&CanHandle) < 1)
+  {
+  }
+
+  /* Start the Transmission process */
+  if (HAL_CAN_AddTxMessage(&CanHandle, &TxHeader, (uint8_t*)data, &TxMailbox) != HAL_OK)
+  {
+    /* Transmission request Error */
+    Error_Handler();
+  }
+}
+
+/**
+  * @brief  This function is executed in case of error occurrence.
+  * @param  None
+  * @retval None
+  */
+static void __NO_RETURN Error_Handler(void)
+{
+  while (1)
+  {
+  }
+}
+
+/**
+  * @brief  Configures the CAN.
+  * @param  None
+  * @retval None
+  */
+void can_config(void)
+{
+  CAN_FilterTypeDef  sFilterConfig;
+
+  /* Configure the CAN peripheral */
+  CanHandle.Instance = CANx;
+
+  CanHandle.MspInitCallback = CAN_MspInit;
+  CanHandle.MspDeInitCallback = CAN_MspDeInit;
+
+  CanHandle.Init.TimeTriggeredMode = DISABLE;
+  CanHandle.Init.AutoBusOff = ENABLE;
+  CanHandle.Init.AutoWakeUp = DISABLE;
+  CanHandle.Init.AutoRetransmission = ENABLE;
+  CanHandle.Init.ReceiveFifoLocked = DISABLE;
+  CanHandle.Init.TransmitFifoPriority = DISABLE;
+  CanHandle.Init.Mode = CAN_MODE_NORMAL;
+  CanHandle.Init.SyncJumpWidth = CAN_SJW_1TQ;
+  CanHandle.Init.TimeSeg1 = CAN_BS1_6TQ;
+  CanHandle.Init.TimeSeg2 = CAN_BS2_5TQ;
+  CanHandle.Init.Prescaler = 4;
+
+  if (HAL_CAN_Init(&CanHandle) != HAL_OK)
+  {
+    /* Initialization Error */
+    Error_Handler();
+  }
+
+  /* Configure the CAN Filter */
+  sFilterConfig.FilterBank = 0;
+  sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK;
+  sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT;
+  sFilterConfig.FilterIdHigh = 0x0000;
+  sFilterConfig.FilterIdLow = 0x0310;
+  sFilterConfig.FilterMaskIdHigh = 0x0000;
+  sFilterConfig.FilterMaskIdLow = 0x07F8;
+  sFilterConfig.FilterFIFOAssignment = CAN_RX_FIFO0;
+  sFilterConfig.FilterActivation = ENABLE;
+  sFilterConfig.SlaveStartFilterBank = 14;
+
+  if (HAL_CAN_ConfigFilter(&CanHandle, &sFilterConfig) != HAL_OK)
+  {
+    /* Filter configuration Error */
+    Error_Handler();
+  }
+
+  if (HAL_CAN_RegisterCallback(&CanHandle, HAL_CAN_RX_FIFO0_MSG_PENDING_CB_ID, CAN_RxFifo0MsgPendingCallback) != HAL_OK)
+  {
+    Error_Handler();
+  }
+
+  if (HAL_CAN_RegisterCallback(&CanHandle, HAL_CAN_TX_MAILBOX0_COMPLETE_CB_ID, CAN_TxMailboxCompleteCallback) != HAL_OK)
+  {
+    Error_Handler();
+  }
+
+  if (HAL_CAN_RegisterCallback(&CanHandle, HAL_CAN_TX_MAILBOX1_COMPLETE_CB_ID, CAN_TxMailboxCompleteCallback) != HAL_OK)
+  {
+    Error_Handler();
+  }
+
+  if (HAL_CAN_RegisterCallback(&CanHandle, HAL_CAN_TX_MAILBOX2_COMPLETE_CB_ID, CAN_TxMailboxCompleteCallback) != HAL_OK)
+  {
+    Error_Handler();
+  }
+
+  /* Start the CAN peripheral */
+  if (HAL_CAN_Start(&CanHandle) != HAL_OK)
+  {
+    /* Start Error */
+    Error_Handler();
+  }
+
+  /* Activate CAN RX notification */
+  if (HAL_CAN_ActivateNotification(&CanHandle, CAN_IT_RX_FIFO0_MSG_PENDING) != HAL_OK)
+  {
+    /* Notification Error */
+    Error_Handler();
+  }
+
+  /* Activate CAN TX notification */
+  if (HAL_CAN_ActivateNotification(&CanHandle, CAN_IT_TX_MAILBOX_EMPTY) != HAL_OK)
+  {
+    /* Notification Error */
+    Error_Handler();
+  }
+
+  /* Configure Transmission process */
+  TxHeader.StdId = 0x321;
+  TxHeader.ExtId = 0x01;
+  TxHeader.RTR = CAN_RTR_DATA;
+  TxHeader.IDE = CAN_ID_STD;
+  TxHeader.DLC = 2;
+  TxHeader.TransmitGlobalTime = DISABLE;
+}
+
+/**
+  * @brief  Rx Fifo 0 message pending callback in non blocking mode
+  * @param  CanHandle: pointer to a CAN_HandleTypeDef structure that contains
+  *         the configuration information for the specified CAN.
+  * @retval None
+  */
+static void CAN_RxFifo0MsgPendingCallback(CAN_HandleTypeDef *CanHandle)
+{
+  /* Get RX message */
+  if (HAL_CAN_GetRxMessage(CanHandle, CAN_RX_FIFO0, &RxHeader, RxData) != HAL_OK)
+  {
+    /* Reception Error */
+    Error_Handler();
+  }
+
+  if (RxHeader.IDE == CAN_ID_STD &&
+      (RxHeader.StdId == CAN_ID_COMMAND_STW_TO_BACK ||
+       RxHeader.StdId == CAN_ID_FEEDBACK_STW_TO_BACK))
+  {
+    can_feedc0de_handle_frame(RxHeader.StdId, RxData, dlc_to_len(RxHeader.DLC));
+  }
+
+  // slightly yucky, but we don't want to block inside the IRQ handler
+  if (HAL_CAN_GetTxMailboxesFreeLevel(CanHandle) >= 2)
+  {
+    can_feedc0de_poll();
+  }
+}
+
+static void CAN_TxMailboxCompleteCallback(CAN_HandleTypeDef *hcan)
+{
+  // slightly yucky, but we don't want to block inside the IRQ handler
+  if (HAL_CAN_GetTxMailboxesFreeLevel(hcan) >= 2)
+  {
+    can_feedc0de_poll();
+  }
+}
+
+/**
+  * @brief CAN MSP Initialization
+  *        This function configures the hardware resources used in this example:
+  *           - Peripheral's clock enable
+  *           - Peripheral's GPIO Configuration
+  *           - NVIC configuration for DMA interrupt request enable
+  * @param hcan: CAN handle pointer
+  * @retval None
+  */
+static void CAN_MspInit(CAN_HandleTypeDef *hcan)
+{
+  GPIO_InitTypeDef   GPIO_InitStruct;
+
+  /*##-1- Enable peripherals and GPIO Clocks #################################*/
+  /* CAN1 Periph clock enable */
+  CANx_CLK_ENABLE();
+  /* Enable GPIO clock ****************************************/
+  CANx_GPIO_CLK_ENABLE();
+  /* Enable AFIO clock and Remap CAN PINs to PB8 and PB9*******/
+  CANx_AFIO_REMAP_CLK_ENABLE();
+  CANx_AFIO_REMAP_RX_TX_PIN();
+
+  /*##-2- Configure peripheral GPIO ##########################################*/
+  /* CAN1 TX GPIO pin configuration */
+  GPIO_InitStruct.Pin = CANx_TX_PIN;
+  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
+  GPIO_InitStruct.Pull = GPIO_PULLUP;
+
+  HAL_GPIO_Init(CANx_TX_GPIO_PORT, &GPIO_InitStruct);
+
+  /* CAN1 RX GPIO pin configuration */
+  GPIO_InitStruct.Pin = CANx_RX_PIN;
+  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
+  GPIO_InitStruct.Pull = GPIO_PULLUP;
+
+  HAL_GPIO_Init(CANx_RX_GPIO_PORT, &GPIO_InitStruct);
+
+  /*##-3- Configure the NVIC #################################################*/
+  /* NVIC configuration for CAN1 Reception complete interrupt */
+  HAL_NVIC_SetPriority(CANx_RX_IRQn, 1, 0);
+  HAL_NVIC_EnableIRQ(CANx_RX_IRQn);
+
+  HAL_NVIC_SetPriority(CANx_TX_IRQn, 1, 0);
+  HAL_NVIC_EnableIRQ(CANx_TX_IRQn);
+}
+
+/**
+  * @brief CAN MSP De-Initialization
+  *        This function frees the hardware resources used in this example:
+  *          - Disable the Peripheral's clock
+  *          - Revert GPIO to their default state
+  * @param hcan: CAN handle pointer
+  * @retval None
+  */
+static void CAN_MspDeInit(CAN_HandleTypeDef *hcan)
+{
+  /*##-1- Reset peripherals ##################################################*/
+  CANx_FORCE_RESET();
+  CANx_RELEASE_RESET();
+
+  /*##-2- Disable peripherals and GPIO Clocks ################################*/
+  /* De-initialize the CAN1 TX GPIO pin */
+  HAL_GPIO_DeInit(CANx_TX_GPIO_PORT, CANx_TX_PIN);
+  /* De-initialize the CAN1 RX GPIO pin */
+  HAL_GPIO_DeInit(CANx_RX_GPIO_PORT, CANx_RX_PIN);
+
+  /*##-4- Disable the NVIC for CAN reception #################################*/
+  HAL_NVIC_DisableIRQ(CANx_RX_IRQn);
+}
+
+/**
+* @brief  This function handles CAN1 RX0 interrupt request.
+* @param  None
+* @retval None
+*/
+void CANx_RX_IRQHandler(void)
+{
+  HAL_CAN_IRQHandler(&CanHandle);
+}
+
+void CANx_TX_IRQHandler(void)
+{
+  HAL_CAN_IRQHandler(&CanHandle);
+}

can.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#define CAN_ID_COMMAND_STW_TO_BACK  0x311
+#define CAN_ID_COMMAND_BACK_TO_STW  0x312
+#define CAN_ID_COMMAND_STW_TO_FRONT 0x315
+#define CAN_ID_COMMAND_FRONT_TO_STW 0x316
+
+#define CAN_ID_FEEDBACK_STW_TO_BACK  0x319
+#define CAN_ID_FEEDBACK_BACK_TO_STW  0x31A
+#define CAN_ID_FEEDBACK_STW_TO_FRONT 0x31D
+#define CAN_ID_FEEDBACK_FRONT_TO_STW 0x31E
+
+#define CAN_ID_HB_BACK_TO_STW       0x331
+#define CAN_ID_HB_FRONT_TO_STW      0x333
+
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+void can_config(void);
+void can_test(void);
+void can_tx(uint16_t id, const uint8_t* data, uint8_t len);
+
+
+#ifdef __cplusplus
+}
+#endif

can_fc.h

@@ -0,0 +1,216 @@
+#pragma once
+
+#ifdef __cplusplus
+#include <cstdint>
+#include <cstddef>
+#include <cstring>
+#include <algorithm>
+
+#include "can.h"
+
+//#define FC_STRICT
+
+#define FC_PROTOCOL_ERROR()
+#define Error_Handler() while(1)
+
+constexpr const uint8_t FC_CHUNK_SIZE = 7;
+constexpr const uint8_t FC_TAG_INIT = 0x45;
+constexpr const uint8_t FC_TAG_END = 0x7d;
+
+static uint8_t next_tag(uint8_t tag)
+{
+  if (tag == 0)
+  {
+    return FC_TAG_INIT;
+  }
+  else
+  {
+    return tag + 0x04;
+  }
+}
+
+class FCSender
+{
+public:
+  FCSender(uint16_t id) : id(id)
+  {
+  }
+
+  bool tx_pending()
+  {
+    return pos_sent != len && pos_sent == pos_acked;
+  }
+
+  bool transfer_in_progress()
+  {
+    return data != nullptr && pos_acked != len;
+  }
+
+  bool transfer_finished()
+  {
+    return data != nullptr && pos_acked == len;
+  }
+
+  void reset(const uint8_t* data, size_t len)
+  {
+    pos_sent = 0;
+    pos_acked = 0;
+    tag_sent = 0;
+
+    this->data = data;
+    this->len = len;
+  }
+
+  void handle_frame(const uint8_t* payload, uint8_t payload_len)
+  {
+    if (pos_sent == 0)
+      return;
+
+    if (payload_len != 1)
+      return;
+
+    if (payload[0] != tag_sent)
+      return;
+
+    pos_acked = pos_sent;
+  }
+
+  void tx()
+  {
+    uint8_t payload[1 + FC_CHUNK_SIZE];
+
+    // Still waiting for ack, or done transmitting
+    if (!tx_pending())
+      return;
+
+    size_t new_pos_sent = std::min(pos_sent + FC_CHUNK_SIZE, len);
+    uint8_t sent_size = new_pos_sent - pos_sent;
+    uint8_t new_tag_sent = next_tag(tag_sent);
+    if (new_tag_sent == FC_TAG_END)
+      Error_Handler();
+
+    payload[0] = new_tag_sent;
+    memcpy(&payload[1], data + pos_sent, sent_size);
+    can_tx(id, payload, 1 + sent_size);
+
+    pos_sent = new_pos_sent;
+    tag_sent = new_tag_sent;
+  }
+
+private:
+  uint16_t id;
+  const uint8_t* data;
+  size_t len;
+  size_t pos_sent;
+  size_t pos_acked;
+  uint8_t tag_sent;
+};
+
+class FCReceiver
+{
+public:
+  FCReceiver(uint16_t id, uint8_t* data, size_t len) : id(id)
+  {
+    reset(data, len);
+  }
+
+  bool ack_pending()
+  {
+    return pos_received != pos_acked;
+  }
+
+  bool transfer_in_progress()
+  {
+    return ready && data != nullptr && pos_acked != len;
+  }
+
+  bool transfer_finished()
+  {
+    return ready && data != nullptr && pos_acked == len;
+  }
+
+  void reset(uint8_t* data, size_t len)
+  {
+    // Poor man's mutex
+    ready = false;
+
+    pos_received = 0;
+    pos_acked = 0;
+    tag_expected = next_tag(0);
+
+    this->data = data;
+    this->len = len;
+
+    ready = true;
+  }
+
+  void handle_frame(const uint8_t* payload, uint8_t payload_len)
+  {
+    if (!transfer_in_progress())
+      return;
+
+    if (tag_expected == FC_TAG_END)
+      return;
+
+    if (payload_len < 1)
+      return;
+
+    // Reset receiver if frame with FC_TAG_INIT received when expecting different one
+    if (payload[0] == FC_TAG_INIT && tag_expected != FC_TAG_INIT)
+      reset(data, len);
+
+    // Don't accept new data if we haven't acked the previous data yet
+    if (ack_pending())
+      return;
+
+    uint8_t data_len = payload_len - 1;
+    if (data_len > len - pos_received)
+      return;
+
+    // Ignore all other tags
+    if (payload[0] != tag_expected)
+      return;
+
+    memcpy(&data[pos_received], &payload[1], data_len);
+
+    pos_received += data_len;
+  }
+
+  void ack()
+  {
+    uint8_t payload[1];
+
+    if (!ack_pending())
+      return;
+
+    // Poor man's mutex
+    ready = false;
+
+    // ISR may have called reset() in the mean time
+    if (!ack_pending())
+    {
+      ready = true;
+      return;
+    }
+
+    payload[0] = tag_expected;
+    can_tx(id, payload, sizeof(payload));
+
+    pos_acked = pos_received;
+    tag_expected = next_tag(tag_expected);
+
+    ready = true;
+  }
+
+private:
+  bool ready;
+
+  uint16_t id;
+  uint8_t* data;
+  size_t len;
+  size_t pos_received;
+  size_t pos_acked;
+  uint8_t tag_expected;
+};
+
+#endif // __cplusplus

can_feedc0de.cpp

@@ -0,0 +1,69 @@
+#include <cstdint>
+#include <cstddef>
+#include <cstring>
+
+#include "protocol.h"
+#include "can_fc.h"
+
+#include "can_feedc0de.h"
+
+
+static_assert((sizeof(Command) + FC_CHUNK_SIZE - 1) / FC_CHUNK_SIZE < 15);
+
+void CANFeedc0de::poll()
+{
+  if (feedc0de_fcs.tx_pending())
+    feedc0de_fcs.tx();
+
+  if (feedc0de_fcr.ack_pending())
+    feedc0de_fcr.ack();
+}
+
+void CANFeedc0de::send_feedback(const Feedback& in)
+{
+  feedback = in;
+  feedc0de_fcs.reset(((uint8_t*)&feedback) + 2, sizeof(feedback) - 4);
+}
+
+bool CANFeedc0de::get_command(Command& out)
+{
+  if (!feedc0de_fcr.transfer_finished())
+    return false;
+
+  out = command;
+  feedc0de_fcr.reset(((uint8_t*)&command) + 2, sizeof(command) - 4);
+
+  return true;
+}
+
+void CANFeedc0de::handle_frame(uint16_t id, uint8_t* frame, uint8_t len)
+{
+  switch (id)
+  {
+  case CAN_ID_FEEDBACK_STW_TO_BACK:
+    feedc0de_fcs.handle_frame(frame, len);
+    break;
+  case CAN_ID_COMMAND_STW_TO_BACK:
+    feedc0de_fcr.handle_frame(frame, len);
+    break;
+  default:
+    Error_Handler();
+  }
+}
+
+extern "C"
+{
+
+void can_feedc0de_handle_frame(uint16_t id, uint8_t* frame, uint8_t len)
+{
+  extern CANFeedc0de can_feedc0de;
+  can_feedc0de.handle_frame(id, frame, len);
+}
+
+void can_feedc0de_poll()
+{
+  extern CANFeedc0de can_feedc0de;
+  can_feedc0de.poll();
+}
+
+}

can_feedc0de.h

@@ -0,0 +1,31 @@
+#pragma once
+
+#ifdef __cplusplus
+#include <cstdint>
+#include "protocol.h"
+#include "can_fc.h"
+class CANFeedc0de
+{
+public:
+  void poll();
+  void handle_frame(uint16_t id, uint8_t* frame, uint8_t len);
+  void send_feedback(const Feedback& in);
+  bool get_command(Command& out);
+private:
+  Command command;
+  Feedback feedback;
+
+  FCSender feedc0de_fcs = FCSender(CAN_ID_FEEDBACK_BACK_TO_STW);
+  FCReceiver feedc0de_fcr = FCReceiver(CAN_ID_COMMAND_BACK_TO_STW, ((uint8_t *)&command) + 2, sizeof(command) - 4);
+};
+
+extern "C"
+{
+#endif
+
+void can_feedc0de_handle_frame(uint16_t id, uint8_t* frame, uint8_t len);
+void can_feedc0de_poll();
+
+#ifdef __cplusplus
+}
+#endif

main.cpp

@@ -34,6 +34,14 @@ extern "C" {
 extern const P rtP_Left; // default settings defined in BLDC_controller_data.c
 }
 
+#ifdef FEATURE_CAN
+#include "can.h"
+#include "can_feedc0de.h"
+
+CANFeedc0de can_feedc0de;
+
+#endif
+
 namespace {
 TIM_HandleTypeDef htim_right;
 TIM_HandleTypeDef htim_left;
@@ -104,8 +112,6 @@ struct {
 Command command;
 Feedback feedback;
 
-
-
 void filtLowPass32(int16_t u, uint16_t coef, int32_t *y);
 
 void SystemClock_Config();
@@ -222,6 +228,11 @@ int main()
     int pwm = 0;
     int8_t dir = 1;
 #else
+
+    can_config();
+    MODIFY_REG(RCC->CR, RCC_CR_HSITRIM, (0x1aU << RCC_CR_HSITRIM_Pos));
+
+#ifndef FEATURE_CAN
     HAL_UART_Receive_DMA(&huart2, (uint8_t *)&command, sizeof(command));
 #endif
 
@@ -265,6 +276,7 @@ int main()
         board_temp_deg_c    = (TEMP_CAL_HIGH_DEG_C - TEMP_CAL_LOW_DEG_C) * (board_temp_adcFilt - TEMP_CAL_LOW_ADC) / (TEMP_CAL_HIGH_ADC - TEMP_CAL_LOW_ADC) + TEMP_CAL_LOW_DEG_C;
 
         sendFeedback();
+        can_feedc0de.poll();
 
 #ifdef FEATURE_BUTTON
         if (HAL_GPIO_ReadPin(BUTTON_PORT, BUTTON_PIN))
@@ -1049,6 +1061,9 @@ void parseCommand()
 {
     bool any_parsed{false};
 
+#ifdef FEATURE_CAN
+    any_parsed = can_feedc0de.get_command(command);
+#else
     for (int i = 0; i < 1; i++)
     {
         if (command.start != Command::VALID_HEADER)
@@ -1058,6 +1073,13 @@ void parseCommand()
         if (command.checksum != checksum)
             continue;
 
+        any_parsed = true;
+        break;
+    }
+#endif
+
+    if (any_parsed)
+    {
         left.state = command.left;
         right.state = command.right;
 
@@ -1070,12 +1092,8 @@ void parseCommand()
 
         command.start     = Command::INVALID_HEADER; // Change the Start Frame for timeout detection in the next cycle
         timeoutCntSerial  = 0;                       // Reset the timeout counter
-
-        any_parsed = true;
-        break;
     }
-
+    else
-    if (!any_parsed)
     {
         if (timeoutCntSerial++ >= 100) // Timeout qualification
         {
@@ -1087,58 +1105,69 @@ void parseCommand()
 
             HAL_GPIO_WritePin(LED_PORT, LED_PIN, GPIO_PIN_RESET);
 
+#ifndef FEATURE_CAN
             // Check periodically the received Start Frame. Try to re-sync by reseting the DMA
             if (main_loop_counter % 25 == 0)
             {
                 HAL_UART_DMAStop(&huart2);
                 HAL_UART_Receive_DMA(&huart2, (uint8_t *)&command, sizeof(command));
             }
+#endif
         }
     }
 }
 
 void sendFeedback()
 {
-    if (main_loop_counter % 50 == 0) {    // Send data periodically
+    // Send data periodically
-        if(UART_DMA_CHANNEL->CNDTR == 0) {
+    if (main_loop_counter % 50 != 0)
-            feedback.start = Feedback::VALID_HEADER;
+        return;
 
-            feedback.left.angle = left.rtY.a_elecAngle;
+#ifndef FEATURE_CAN
-            feedback.right.angle = right.rtY.a_elecAngle;
+    if (UART_DMA_CHANNEL->CNDTR != 0)
+        return;
+#endif
 
-            feedback.left.speed = left.rtY.n_mot;
+    feedback.start = Feedback::VALID_HEADER;
-            feedback.right.speed = right.rtY.n_mot;
 
-            feedback.left.error = left.rtY.z_errCode;
+    feedback.left.angle = left.rtY.a_elecAngle;
-            feedback.right.error = right.rtY.z_errCode;
+    feedback.right.angle = right.rtY.a_elecAngle;
 
-            feedback.left.current = left.rtU.i_DCLink;
+    feedback.left.speed = left.rtY.n_mot;
-            feedback.right.current = right.rtU.i_DCLink;
+    feedback.right.speed = right.rtY.n_mot;
 
-            feedback.left.chops = left.chops;
+    feedback.left.error = left.rtY.z_errCode;
-            feedback.right.chops = right.chops;
+    feedback.right.error = right.rtY.z_errCode;
-            left.chops = 0;
-            right.chops = 0;
 
-            feedback.left.hallA = left.rtU.b_hallA;
+    feedback.left.current = left.rtU.i_DCLink;
-            feedback.left.hallB = left.rtU.b_hallB;
+    feedback.right.current = right.rtU.i_DCLink;
-            feedback.left.hallC = left.rtU.b_hallC;
-            feedback.right.hallA = right.rtU.b_hallA;
-            feedback.right.hallB = right.rtU.b_hallB;
-            feedback.right.hallC = right.rtU.b_hallC;
 
-            feedback.batVoltage = batVoltage * BAT_CALIB_REAL_VOLTAGE / BAT_CALIB_ADC;
+    feedback.left.chops = left.chops;
-            feedback.boardTemp = board_temp_deg_c;
+    feedback.right.chops = right.chops;
-            feedback.timeoutCntSerial = timeoutCntSerial;
+    left.chops = 0;
+    right.chops = 0;
 
-            feedback.checksum = calculateChecksum(feedback);
+    feedback.left.hallA = left.rtU.b_hallA;
+    feedback.left.hallB = left.rtU.b_hallB;
+    feedback.left.hallC = left.rtU.b_hallC;
+    feedback.right.hallA = right.rtU.b_hallA;
+    feedback.right.hallB = right.rtU.b_hallB;
+    feedback.right.hallC = right.rtU.b_hallC;
 
-            UART_DMA_CHANNEL->CCR    &= ~DMA_CCR_EN;
+    feedback.batVoltage = batVoltage * BAT_CALIB_REAL_VOLTAGE / BAT_CALIB_ADC;
-            UART_DMA_CHANNEL->CNDTR   = sizeof(feedback);
+    feedback.boardTemp = board_temp_deg_c;
-            UART_DMA_CHANNEL->CMAR    = uint64_t(&feedback);
+    feedback.timeoutCntSerial = timeoutCntSerial;
-            UART_DMA_CHANNEL->CCR    |= DMA_CCR_EN;
+
-        }
+    feedback.checksum = calculateChecksum(feedback);
-    }
+
+#ifdef FEATURE_CAN
+    can_feedc0de.send_feedback(feedback);
+#else
+    UART_DMA_CHANNEL->CCR    &= ~DMA_CCR_EN;
+    UART_DMA_CHANNEL->CNDTR   = sizeof(feedback);
+    UART_DMA_CHANNEL->CMAR    = uint64_t(&feedback);
+    UART_DMA_CHANNEL->CCR    |= DMA_CCR_EN;
+#endif
 }
 
 } // anonymous namespace

stm32f1xx_hal_conf.h

@@ -36,7 +36,7 @@ extern "C" {
   */
 #define HAL_MODULE_ENABLED
 #define HAL_ADC_MODULE_ENABLED
-/* #define HAL_CAN_MODULE_ENABLED */
+#define HAL_CAN_MODULE_ENABLED
 /* #define HAL_CAN_LEGACY_MODULE_ENABLED */
 /* #define HAL_CEC_MODULE_ENABLED */
 #define HAL_CORTEX_MODULE_ENABLED
@@ -129,7 +129,7 @@ extern "C" {
 #define  PREFETCH_ENABLE              1U
 
 #define  USE_HAL_ADC_REGISTER_CALLBACKS         0U /* ADC register callback disabled       */
-#define  USE_HAL_CAN_REGISTER_CALLBACKS         0U /* CAN register callback disabled       */
+#define  USE_HAL_CAN_REGISTER_CALLBACKS         1U /* CAN register callback disabled       */
 #define  USE_HAL_CEC_REGISTER_CALLBACKS         0U /* CEC register callback disabled       */
 #define  USE_HAL_DAC_REGISTER_CALLBACKS         0U /* DAC register callback disabled       */
 #define  USE_HAL_ETH_REGISTER_CALLBACKS         0U /* ETH register callback disabled       */