// We have our own version of CAN transmit so we can handle Timeout=0 correctly.
STATIC HAL_StatusTypeDef CAN_Transmit(CAN_HandleTypeDef *hcan, uint32_t Timeout) {
uint32_t transmitmailbox;
uint32_t tickstart;
uint32_t rqcpflag;
uint32_t txokflag;
// Check the parameters
assert_param(IS_CAN_IDTYPE(hcan->pTxMsg->IDE));
assert_param(IS_CAN_RTR(hcan->pTxMsg->RTR));
assert_param(IS_CAN_DLC(hcan->pTxMsg->DLC));
// Select one empty transmit mailbox
if ((hcan->Instance->TSR&CAN_TSR_TME0) == CAN_TSR_TME0) {
transmitmailbox = CAN_TXMAILBOX_0;
rqcpflag = CAN_FLAG_RQCP0;
txokflag = CAN_FLAG_TXOK0;
} else if ((hcan->Instance->TSR&CAN_TSR_TME1) == CAN_TSR_TME1) {
transmitmailbox = CAN_TXMAILBOX_1;
rqcpflag = CAN_FLAG_RQCP1;
txokflag = CAN_FLAG_TXOK1;
} else if ((hcan->Instance->TSR&CAN_TSR_TME2) == CAN_TSR_TME2) {
transmitmailbox = CAN_TXMAILBOX_2;
rqcpflag = CAN_FLAG_RQCP2;
txokflag = CAN_FLAG_TXOK2;
} else {
transmitmailbox = CAN_TXSTATUS_NOMAILBOX;
}
if (transmitmailbox != CAN_TXSTATUS_NOMAILBOX) {
// Set up the Id
hcan->Instance->sTxMailBox[transmitmailbox].TIR &= CAN_TI0R_TXRQ;
if (hcan->pTxMsg->IDE == CAN_ID_STD) {
assert_param(IS_CAN_STDID(hcan->pTxMsg->StdId));
hcan->Instance->sTxMailBox[transmitmailbox].TIR |= ((hcan->pTxMsg->StdId << 21) | \
hcan->pTxMsg->RTR);
} else {
assert_param(IS_CAN_EXTID(hcan->pTxMsg->ExtId));
hcan->Instance->sTxMailBox[transmitmailbox].TIR |= ((hcan->pTxMsg->ExtId << 3) | \
hcan->pTxMsg->IDE | \
hcan->pTxMsg->RTR);
}
// Set up the DLC
hcan->pTxMsg->DLC &= (uint8_t)0x0000000F;
hcan->Instance->sTxMailBox[transmitmailbox].TDTR &= (uint32_t)0xFFFFFFF0;
hcan->Instance->sTxMailBox[transmitmailbox].TDTR |= hcan->pTxMsg->DLC;
// Set up the data field
hcan->Instance->sTxMailBox[transmitmailbox].TDLR = (((uint32_t)hcan->pTxMsg->Data[3] << 24) |
((uint32_t)hcan->pTxMsg->Data[2] << 16) |
((uint32_t)hcan->pTxMsg->Data[1] << 8) |
((uint32_t)hcan->pTxMsg->Data[0]));
hcan->Instance->sTxMailBox[transmitmailbox].TDHR = (((uint32_t)hcan->pTxMsg->Data[7] << 24) |
((uint32_t)hcan->pTxMsg->Data[6] << 16) |
((uint32_t)hcan->pTxMsg->Data[5] << 8) |
((uint32_t)hcan->pTxMsg->Data[4]));
// Request transmission
hcan->Instance->sTxMailBox[transmitmailbox].TIR |= CAN_TI0R_TXRQ;
if (Timeout == 0) {
return HAL_OK;
}
// Get tick
tickstart = HAL_GetTick();
// Check End of transmission flag
while (!(__HAL_CAN_TRANSMIT_STATUS(hcan, transmitmailbox))) {
// Check for the Timeout
if (Timeout != HAL_MAX_DELAY) {
if ((HAL_GetTick() - tickstart) > Timeout) {
// When the timeout expires, we try to abort the transmission of the packet
__HAL_CAN_CANCEL_TRANSMIT(hcan, transmitmailbox);
while (!__HAL_CAN_GET_FLAG(hcan, rqcpflag)) {
}
if (__HAL_CAN_GET_FLAG(hcan, txokflag)) {
// The abort attempt failed and the message was sent properly
return HAL_OK;
} else {
return HAL_TIMEOUT;
}
}
}
}
return HAL_OK;
} else {
return HAL_BUSY;
}
}
int __start(void) {
const volatile uint32_t *src;
volatile uint32_t *dest;
/* Set up BSS and copy data from flash */
for (src = &_eronly, dest = &_sdata; dest < &_edata;) {
*dest++ = *src++;
}
for (dest = &_sbss; dest < &_ebss;) {
*dest++ = 0;
}
SystemInit();
HAL_Init();
/* Configure the system clock */
SystemClock_Config();
/*
Make sure the flash option bytes are set such that we don't re-enter
bootloader mode
*/
set_dfu_option_bytes(0u);
MX_USB_DEVICE_Init();
/* Configure GPIO for the CAN_SILENT signal */
GPIO_InitTypeDef GPIO_InitStruct;
/* GPIO Ports Clock Enable */
__GPIOA_CLK_ENABLE();
__GPIOB_CLK_ENABLE();
__CRS_CLK_ENABLE();
/*Configure GPIO pin : PB7 */
GPIO_InitStruct.Pin = GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_PULLDOWN;
GPIO_InitStruct.Speed = GPIO_SPEED_LOW;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/**CAN GPIO Configuration
PB8 ------> CAN_RX
PB9 ------> CAN_TX
*/
GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF4_CAN;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* Configure the bxCAN transceiver */
CAN_HandleTypeDef hcan;
__CAN_CLK_ENABLE();
hcan.Instance = CAN;
hcan.Init.Mode = CAN_MODE_SILENT;
hcan.Init.TTCM = DISABLE;
hcan.Init.ABOM = ENABLE;
hcan.Init.AWUM = ENABLE;
hcan.Init.NART = DISABLE;
hcan.Init.RFLM = DISABLE;
hcan.Init.TXFP = DISABLE;
/* Set the bitrate and init */
set_can_bitrate(&hcan, 1000000u);
CanRxMsgTypeDef rx_msg;
hcan.pRxMsg = &rx_msg;
CanTxMsgTypeDef tx_msg;
hcan.pTxMsg = &tx_msg;
CAN_FilterConfTypeDef filter;
filter.FilterNumber = 0;
filter.FilterMode = CAN_FILTERMODE_IDMASK;
filter.FilterScale = CAN_FILTERSCALE_32BIT;
filter.FilterFIFOAssignment = CAN_FILTER_FIFO0;
filter.FilterActivation = ENABLE;
filter.BankNumber = 0;
filter.FilterMaskIdLow = filter.FilterIdLow = filter.FilterMaskIdHigh =
filter.FilterIdHigh = 0;
HAL_CAN_ConfigFilter(&hcan, &filter);
__HAL_UNLOCK(&hcan);
/*
Now that USB is active, we need to sync with the 1 kHz SOF packets to
tune the HSI48 so it's accurate enough not to disrupt the CAN bus.
*/
RCC_CRSInitTypeDef crs_config;
crs_config.Prescaler = RCC_CRS_SYNC_DIV1;
crs_config.Source = RCC_CRS_SYNC_SOURCE_USB;
crs_config.Polarity = RCC_CRS_SYNC_POLARITY_RISING;
crs_config.ReloadValue = RCC_CRS_RELOADVALUE_DEFAULT;
crs_config.ErrorLimitValue = RCC_CRS_ERRORLIMIT_DEFAULT;
crs_config.HSI48CalibrationValue = RCC_CRS_HSI48CALIBRATION_DEFAULT;
HAL_RCCEx_CRSConfig(&crs_config);
/* Don't continue unless we're synced */
while (!(HAL_RCCEx_CRSWaitSynchronization(1000000u) & RCC_CRS_SYNCOK));
while (1) {
/* Set up the command record */
size_t i;
uint8_t current_cmd;
uint8_t current_cmd_data[32];
uint8_t current_cmd_data_length;
uint8_t channel_open;
current_cmd = current_cmd_data_length = i = 0;
channel_open = 0;
rx_buffer_length = 0;
while (hUsbDevice_0 && hUsbDevice_0->pClassData) {
/*
If the RX buffer is non-empty, process any commands/messages in it
and then acknowledge the transfer to the USB stack
*/
if (rx_buffer_length) {
/*
Exit if we've read the entire buffer, or if transmit mailboxes
are full and the current command is a transmit.
*/
for (; i < rx_buffer_length &&
((current_cmd != 't' && current_cmd != 'T') ||
__HAL_CAN_GET_FLAG(&hcan, CAN_FLAG_TME0)); i++) {
if (rx_buffer[i] == '\r') {
uint8_t *buf = active_buffer ? tx_buffer_1 :
tx_buffer_0;
/* End of command -- process and reset state */
switch (current_cmd) {
case 'S':
/*
Setup bitrate -- data should be a number from
0 to 8.
*/
if (current_cmd_data[0] < '0' ||
current_cmd_data[0] > '8') {
buf[active_buffer_length++] = '\a';
} else if (set_can_bitrate(
&hcan,
bitrate_lookup[current_cmd_data[0] - '0'])) {
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 'O':
/*
Open channel -- take CAN out of silent mode
and start receiving.
*/
if (!channel_open) {
channel_open = 1;
set_can_silent(&hcan, 0);
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 'L':
/*
Open in listen-only -- CAN should already be
in silent mode but just make sure.
*/
if (!channel_open) {
channel_open = 1;
set_can_silent(&hcan, 1);
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 'C':
/*
Close channel -- put CAN back in silent mode.
*/
if (channel_open) {
channel_open = 0;
set_can_silent(&hcan, 1);
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 'V':
/* Hardware version */
buf[active_buffer_length++] = 'V';
buf[active_buffer_length++] = '0';
buf[active_buffer_length++] = '0';
buf[active_buffer_length++] = '0';
buf[active_buffer_length++] = '1';
buf[active_buffer_length++] = '\r';
break;
case 'v':
/* Major/minor version */
buf[active_buffer_length++] = 'v';
buf[active_buffer_length++] = '0';
buf[active_buffer_length++] = '0';
buf[active_buffer_length++] = '0';
buf[active_buffer_length++] = '1';
buf[active_buffer_length++] = '\r';
break;
case 'N':
/* Serial number */
buf[active_buffer_length++] = 'N';
buf[active_buffer_length++] = 'F';
buf[active_buffer_length++] = 'F';
buf[active_buffer_length++] = 'F';
buf[active_buffer_length++] = 'F';
buf[active_buffer_length++] = '\r';
break;
case 'T':
/* Extended message */
if (read_ext_message(&tx_msg, current_cmd_data,
current_cmd_data_length) &&
HAL_CAN_Transmit(&hcan, 0) == HAL_OK) {
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 't':
/* Standard message */
if (read_std_message(&tx_msg, current_cmd_data,
current_cmd_data_length) &&
HAL_CAN_Transmit(&hcan, 0) == HAL_OK) {
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 'R':
/* Extended RTR */
if (read_ext_rtr(&tx_msg, current_cmd_data,
current_cmd_data_length) &&
HAL_CAN_Transmit(&hcan, 0) == HAL_OK) {
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 'r':
/* Standard RTR */
if (read_std_rtr(&tx_msg, current_cmd_data,
current_cmd_data_length) &&
HAL_CAN_Transmit(&hcan, 0) == HAL_OK) {
buf[active_buffer_length++] = '\r';
} else {
buf[active_buffer_length++] = '\a';
}
break;
case '_':
/* Bootloader request */
if (current_cmd_data[0] == '_' &&
current_cmd_data[1] == 'd' &&
current_cmd_data[2] == 'f' &&
current_cmd_data[3] == 'u') {
/*
Set option bytes to force bootloader entry
*/
set_dfu_option_bytes(1u);
NVIC_SystemReset();
} else {
buf[active_buffer_length++] = '\a';
}
break;
case 'F':
/* Read status flags -- return 4 hex digits */
case 'Z':
/* Timestamp on/off -- 0=off, 1=on */
case 'M':
/* Acceptance mask -- 8 hex digits */
case 'm':
/* Acceptance value -- 8 hex digits */
case 's':
/* Set bitrate register -- 6 hex digits */
default:
/* NACK */
buf[active_buffer_length++] = '\a';
break;
}
current_cmd = current_cmd_data_length = 0;
} else if (current_cmd) {
/* Command data -- save it */
current_cmd_data[current_cmd_data_length++] =
rx_buffer[i];
/* Reset command state if the data is too long */
if (current_cmd_data_length == 32u) {
current_cmd = current_cmd_data_length = 0;
}
} else {
/*
The first letter of a line is the command type --
don't bother validating as we can't NACK until the
data has been received.
*/
current_cmd = rx_buffer[i];
}
}
if (i == rx_buffer_length) {
/* Mark last packet as received */
rx_buffer_length = i = 0;
USBD_CDC_ReceivePacket(hUsbDevice_0);
}
}
/*
Check the CAN controller for messages and process them if the
channel is open
*/
if (HAL_CAN_Receive(&hcan, CAN_FIFO0, 0) == HAL_OK && hUsbDevice_0 &&
channel_open) {
/*
Format the message and send it to the host.
The data format for a standard ID message is:
tiiildddddddddddddddd\r
The data format for a standard ID RTR is:
riii\r
The data format for an extended ID message is:
Tiiiiiiiildddddddddddddddd\r
The data format for an extended ID RTR is:
Riiiiiiii\r
*/
uint8_t *write_location;
if (active_buffer_length + EXT_MESSAGE_LEN > TX_BUFFER_SIZE) {
/*
Reset buffer if we're too far behind -- use worst-case
message length for calculation
*/
active_buffer_length = 0;
}
write_location = &((active_buffer ? tx_buffer_1 : tx_buffer_0)[active_buffer_length]);
if (rx_msg.IDE == CAN_ID_EXT && rx_msg.RTR) {
active_buffer_length += write_ext_rtr(
write_location, &rx_msg);
} else if (rx_msg.IDE == CAN_ID_EXT && !rx_msg.RTR) {
active_buffer_length += write_ext_message(
write_location, &rx_msg);
} else if (rx_msg.IDE == CAN_ID_STD && rx_msg.RTR) {
active_buffer_length += write_std_rtr(
write_location, &rx_msg);
} else if (rx_msg.IDE == CAN_ID_STD && !rx_msg.RTR) {
active_buffer_length += write_std_message(
write_location, &rx_msg);
}
}
if (!hUsbDevice_0 || !hUsbDevice_0->pClassData) {
/* Reset TX buffer if USB is not connected */
active_buffer_length = 0;
} else if (active_buffer_length &&
((USBD_CDC_HandleTypeDef*)hUsbDevice_0->pClassData)->TxState == 0) {
/* Transmit the next buffer if one is available */
CDC_Transmit_FS(active_buffer ? tx_buffer_1 : tx_buffer_0,
active_buffer_length);
active_buffer_length = 0;
active_buffer = active_buffer ? 0 : 1;
}
}
}
}