openblt_can.cpp

Go to the documentation of this file.

#include "pch.h"
 
#include "hal.h"
 
#include "can.h"
#include "can_hw.h"
 
extern "C" {
    #include "boot.h"
}
 
// CAN1 PB8+PB9 and CAN2 PB5+PB6 pins are commonly used by Hellen.
// CAN2 PB5+PB13 pins can be used for ST-bootloader compatibility.
//
// Other STM32 CAN pin combinations:
// CAN1_RX: { PI9, PA11, PH14, PD0, PB8 }, CAN1_TX: { PA12, PH13, PD1, PB9 }
// CAN2_RX: { PB5, PB12 }, CAN2_TX: { PB6, PB13 }
 
#ifndef BOOT_COM_CAN_CHANNEL_INDEX
    #error BOOT_COM_CAN_CHANNEL_INDEX is not defined.
#elif (BOOT_COM_CAN_CHANNEL_INDEX == 0)
    #if defined(STM32_CAN_USE_CAN1) || defined(STM32_CAN_USE_FDCAN1)
        #define OPENBLT_CAND CAND1
    #else
        #error STM32_CAN_USE_CAN1/STM32_CAN_USE_FDCAN1 is not enabled for CAN index 0
    #endif
#elif (BOOT_COM_CAN_CHANNEL_INDEX == 1)
    #if defined(STM32_CAN_USE_CAN2) || defined(STM32_CAN_USE_FDCAN2)
        #define OPENBLT_CAND CAND2
    #else
        #error STM32_CAN_USE_CAN2/STM32_CAN_USE_FDCAN2 is not enabled for CAN index 1
    #endif
#else
    #error Unknown BOOT_COM_CAN_CHANNEL_INDEX.
#endif
 
#ifndef CAN_IDE_STD
#define CAN_IDE_STD 0
#endif
 
#ifndef CAN_IDE_EXT
#define CAN_IDE_EXT 1
#endif
 
#if !defined(OPENBLT_CAN_RX_PIN) || !defined(OPENBLT_CAN_RX_PORT) || !defined(OPENBLT_CAN_TX_PIN) || !defined(OPENBLT_CAN_TX_PORT)
#if (BOOT_COM_CAN_CHANNEL_INDEX == 0)
  // default pins for CAN1 (compatible with Hellen)
  #define OPENBLT_CAN_RX_PORT GPIOB
  #define OPENBLT_CAN_RX_PIN 8
  #define OPENBLT_CAN_TX_PORT GPIOB
  #define OPENBLT_CAN_TX_PIN 9
#elif (BOOT_COM_CAN_CHANNEL_INDEX == 1)
  // default pins for CAN2 (compatible with ST-bootloader)
  #define OPENBLT_CAN_RX_PORT GPIOB
  #define OPENBLT_CAN_RX_PIN 5
  #define OPENBLT_CAN_TX_PORT GPIOB
  #define OPENBLT_CAN_TX_PIN 13
#endif
#endif
 
extern const CANConfig *findCanConfig(can_baudrate_e rate);
 
/************************************************************************************//**
** \brief     Initializes the CAN controller and synchronizes it to the CAN bus.
** \return    none.
**
****************************************************************************************/
extern "C" void CanInit(void) {
    // init pins
    palSetPadMode(OPENBLT_CAN_TX_PORT, OPENBLT_CAN_TX_PIN, PAL_MODE_ALTERNATE(EFI_CAN_TX_AF));
    palSetPadMode(OPENBLT_CAN_RX_PORT, OPENBLT_CAN_RX_PIN, PAL_MODE_ALTERNATE(EFI_CAN_RX_AF));
 
    auto cfg = findCanConfig(B500KBPS);
    canStart(&OPENBLT_CAND, cfg);
}
 
 
/************************************************************************************//**
** \brief     Transmits a packet formatted for the communication interface.
** \param     data Pointer to byte array with data that it to be transmitted.
** \param     len  Number of bytes that are to be transmitted.
** \return    none.
**
****************************************************************************************/
extern "C" void CanTransmitPacket(blt_int8u *data, blt_int8u len)
{
    blt_int32u txMsgId = BOOT_COM_CAN_TX_MSG_ID;
    CANTxFrame frame = {};
 
    if ((txMsgId & 0x80000000) == 0)
    {
        /* set the 11-bit CAN identifier. */
        CAN_SID(frame) = txMsgId;
        CAN_ISX(frame) = CAN_IDE_STD;
    }
    else
    {
        txMsgId &= ~0x80000000;
        /* set the 29-bit CAN identifier. */
        CAN_EID(frame) = txMsgId;
        CAN_ISX(frame) = CAN_IDE_EXT;
    }
 
    // Copy data/DLC
    frame.DLC = len;
    memcpy(frame.data8, data, len);
 
    canTransmitTimeout(&OPENBLT_CAND, CAN_ANY_MAILBOX, &frame, TIME_MS2I(100));
}
 
/************************************************************************************//**
** \brief     Receives a communication interface packet if one is present.
** \param     data Pointer to byte array where the data is to be stored.
** \param     len Pointer where the length of the packet is to be stored.
** \return    BLT_TRUE is a packet was received, BLT_FALSE otherwise.
**
****************************************************************************************/
 
#ifdef BOOTLOADER_CAN_LISTENER
extern void boardCanListener(CANRxFrame *frame);
#endif
 
extern "C" blt_bool CanReceivePacket(blt_int8u *data, blt_int8u *len)
{
    constexpr blt_int32u rxMsgId = BOOT_COM_CAN_RX_MSG_ID;
    CANRxFrame frame;
 
    if (MSG_OK != canReceiveTimeout(&OPENBLT_CAND, CAN_ANY_MAILBOX, &frame, TIME_IMMEDIATE)) {
        // no message was waiting
        return BLT_FALSE;
    }
 
    // Check that the ID type matches this frame (std vs ext)
    constexpr bool configuredAsExt = (rxMsgId & 0x80000000) != 0;
    if (configuredAsExt != CAN_ISX(frame)) {
        // Wrong frame type
        goto wrong;
    }
 
    // Check that the frame's ID matches
    if (CAN_ISX(frame)) {
        if (CAN_EID(frame) != (rxMsgId & ~0x80000000)) {
            // Wrong ID
            goto wrong;
        }
    } else {
        if (CAN_SID(frame) != rxMsgId) {
            // Wrong ID
            goto wrong;
        }
    }
 
    // Copy data and length out
    *len = frame.DLC;
    memcpy(data, frame.data8, frame.DLC);
 
    return BLT_TRUE;
 
wrong:
 
#ifdef BOOTLOADER_CAN_LISTENER
    boardCanListener(&frame);
#endif
 
    return BLT_FALSE;
}