Files
panda-meb/board/stm32f4/lluart.h
Adeeb Shihadeh 5ac6305a95 quick garbage collection pass (#2231)
* remove DPANDA

* -22

* lil more

* canfd

* lil more

* update cppcheck

* uart cleanup

* always harness

* sbu sense

* lil more

* enable spi

* rm ENABLE_SPI
2025-07-19 21:05:12 -07:00

32 lines
1.3 KiB
C

// ***************************** Interrupt handlers *****************************
void uart_tx_ring(uart_ring *q){
ENTER_CRITICAL();
// Send out next byte of TX buffer
if (q->w_ptr_tx != q->r_ptr_tx) {
// Only send if transmit register is empty (aka last byte has been sent)
if ((q->uart->SR & USART_SR_TXE) != 0U) {
q->uart->DR = q->elems_tx[q->r_ptr_tx]; // This clears TXE
q->r_ptr_tx = (q->r_ptr_tx + 1U) % q->tx_fifo_size;
}
// Enable TXE interrupt if there is still data to be sent
if(q->r_ptr_tx != q->w_ptr_tx){
q->uart->CR1 |= USART_CR1_TXEIE;
} else {
q->uart->CR1 &= ~USART_CR1_TXEIE;
}
}
EXIT_CRITICAL();
}
// This read after reading SR clears all error interrupts. We don't want compiler warnings, nor optimizations
#define UART_READ_DR(uart) volatile uint8_t t = (uart)->DR; UNUSED(t);
// ***************************** Hardware setup *****************************
#define DIV_(_PCLK_, _BAUD_) (((_PCLK_) * 25U) / (4U * (_BAUD_)))
#define DIVMANT_(_PCLK_, _BAUD_) (DIV_((_PCLK_), (_BAUD_)) / 100U)
#define DIVFRAQ_(_PCLK_, _BAUD_) ((((DIV_((_PCLK_), (_BAUD_)) - (DIVMANT_((_PCLK_), (_BAUD_)) * 100U)) * 16U) + 50U) / 100U)
#define USART_BRR_(_PCLK_, _BAUD_) ((DIVMANT_((_PCLK_), (_BAUD_)) << 4) | (DIVFRAQ_((_PCLK_), (_BAUD_)) & 0x0FU))