/* * usart.c * * Copyright 2017 Edward V. Emelianoff * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA 02110-1301, USA. */ #include "stm32f0.h" #include "hardware.h" #include "proto.h" #include "usart.h" #include "usb.h" #include extern volatile uint32_t Tms; // USART tx DMA 1: DMA1_Channel2, 2: DMA1_Channel4, 3: DMA1_Channel7 static DMA_Channel_TypeDef *USARTDMA[USARTNUM] = { DMA1_Channel2, DMA1_Channel4 #ifdef USART3 ,DMA1_Channel7 #endif }; static USART_TypeDef *USARTs[USARTNUM] = { USART1, USART2 #ifdef USART3 ,USART3 #endif }; static volatile int idatalen[USARTNUM][2] = {0}; // received data line length (including '\n') static volatile int odatalen[USARTNUM][2] = {0}; volatile int linerdy[USARTNUM] = {0}, // received data ready dlen[USARTNUM] = {0}, // length of data (including '\n') in current buffer bufovr[USARTNUM] = {0}, // input buffer overfull txrdy[USARTNUM] = {1,1 // transmission done #ifdef USART3 ,1 #endif } ; int rbufno[USARTNUM] = {0}, tbufno[USARTNUM] = {0}; // current rbuf/tbuf numbers static char rbuf[USARTNUM][2][UARTBUFSZI], tbuf[USARTNUM][2][UARTBUFSZO]; // receive & transmit buffers static char *recvdata[USARTNUM] = {0}; /** * return length of received data (without trailing zero * usartno: 1, 2 or 3 */ int usart_getline(int usartno, char **line){ --usartno; if(bufovr[usartno]){ bufovr[usartno] = 0; linerdy[usartno] = 0; return 0; } *line = recvdata[usartno]; linerdy[usartno] = 0; return dlen[usartno]; } // transmit current tbuf for all USARTs and swap buffers void transmit_tbuf(){ for(int usartno = 0; usartno < USARTNUM; ++usartno){ uint32_t p = 1000000; while(!txrdy[usartno] && --p); if(!txrdy[usartno]) continue; register int l = odatalen[usartno][tbufno[usartno]]; if(!l) continue; txrdy[usartno] = 0; odatalen[usartno][tbufno[usartno]] = 0; USARTDMA[usartno]->CCR &= ~DMA_CCR_EN; USARTDMA[usartno]->CMAR = (uint32_t) tbuf[usartno][tbufno[usartno]]; // mem USARTDMA[usartno]->CNDTR = l; USARTDMA[usartno]->CCR |= DMA_CCR_EN; tbufno[usartno] = !tbufno[usartno]; } } void usart_putchar(int usartno, const char ch){ --usartno; if(odatalen[usartno][tbufno[usartno]] == UARTBUFSZO) transmit_tbuf(); tbuf[usartno][tbufno[usartno]][odatalen[usartno][tbufno[usartno]]++] = ch; } void usart_send(int usartno, const char *str){ --usartno; while(*str){ if(odatalen[usartno][tbufno[usartno]] == UARTBUFSZO) transmit_tbuf(); tbuf[usartno][tbufno[usartno]][odatalen[usartno][tbufno[usartno]]++] = *str++; } } void usart_sendn(int usartno, const char *str, uint32_t L){ --usartno; for(uint32_t i = 0; i < L; ++i){ if(odatalen[usartno][tbufno[usartno]] == UARTBUFSZO) transmit_tbuf(); tbuf[usartno][tbufno[usartno]][odatalen[usartno][tbufno[usartno]]++] = *str++; } } void newline(int usartno){ usart_putchar(usartno, '\n'); transmit_tbuf(); } void usart_setup(){ // USART1: Rx - PA10, Tx - PA9 (AF1) // USART2: Rx - PA3, Tx - PA2 (AF1) // USART3: Rx - PB11, Tx - PB10 (AF4) // setup pins: GPIOA->MODER = (GPIOA->MODER & ~(GPIO_MODER_MODER2|GPIO_MODER_MODER3|GPIO_MODER_MODER9 | GPIO_MODER_MODER10)) | GPIO_MODER_MODER2_AF | GPIO_MODER_MODER3_AF | GPIO_MODER_MODER9_AF | GPIO_MODER_MODER10_AF; GPIOA->AFR[0] = (GPIOA->AFR[0] & ~(GPIO_AFRL_AFRL2 | GPIO_AFRL_AFRL3)) | 1 << (2 * 4) | 1 << (3 * 4); // PA2,3 GPIOA->AFR[1] = (GPIOA->AFR[1] & ~(GPIO_AFRH_AFRH1 | GPIO_AFRH_AFRH2)) | 1 << (1 * 4) | 1 << (2 * 4); // PA9, PA10 // clock RCC->APB2ENR |= RCC_APB2ENR_USART1EN; RCC->APB1ENR |= RCC_APB1ENR_USART2EN; RCC->AHBENR |= RCC_AHBENR_DMA1EN; #ifdef USART3 GPIOB->MODER = (GPIOB->MODER & ~(GPIO_MODER_MODER10 | GPIO_MODER_MODER11)) | GPIO_MODER_MODER10_AF | GPIO_MODER_MODER11_AF; GPIOB->AFR[1] = (GPIOB->AFR[1] & ~(GPIO_AFRH_AFRH2 | GPIO_AFRH_AFRH3)) | 4 << (2 * 4) | 4 << (3 * 4); // PB10, PB11 RCC->APB1ENR |= RCC_APB1ENR_USART3EN; #endif for(int i = 0; i < USARTNUM; ++i){ USARTs[i]->ICR = 0xffffffff; // clear all flags // USARTX Tx DMA USARTDMA[i]->CCR &= ~DMA_CCR_EN; USARTDMA[i]->CPAR = (uint32_t) &USARTs[i]->TDR; // periph USARTDMA[i]->CCR |= DMA_CCR_MINC | DMA_CCR_DIR | DMA_CCR_TCIE; // 8bit, mem++, mem->per, transcompl irq // setup usarts USARTs[i]->BRR = 480000 / 1152; USARTs[i]->CR3 = USART_CR3_DMAT; // enable DMA Tx USARTs[i]->CR1 = USART_CR1_TE | USART_CR1_RE | USART_CR1_UE | USART_CR1_RXNEIE; // 1start,8data,nstop; enable Rx,Tx,USART uint32_t tmout = 16000000; while(!(USARTs[i]->ISR & USART_ISR_TC)){if(--tmout == 0) break;} // polling idle frame Transmission USARTs[i]->ICR = 0xffffffff; // clear all flags again } NVIC_SetPriority(DMA1_Channel2_3_IRQn, 3); NVIC_EnableIRQ(DMA1_Channel2_3_IRQn); NVIC_SetPriority(USART1_IRQn, 0); NVIC_EnableIRQ(USART1_IRQn); NVIC_SetPriority(DMA1_Channel4_5_6_7_IRQn, 3); NVIC_EnableIRQ(DMA1_Channel4_5_6_7_IRQn); NVIC_SetPriority(USART2_IRQn, 0); NVIC_EnableIRQ(USART2_IRQn); #ifdef USART3 NVIC_SetPriority(USART3_4_IRQn, 0); NVIC_EnableIRQ(USART3_4_IRQn); #endif } void usart_stop(){ RCC->APB2ENR &= ~RCC_APB2ENR_USART1EN; RCC->APB1ENR &= ~RCC_APB1ENR_USART2EN; #ifdef USART3 RCC->APB1ENR &= ~RCC_APB1ENR_USART3EN; #endif } static void usart_IRQ(int usartno){ USART_TypeDef *USARTX = USARTs[usartno]; //USND("USART"); USB_sendstr(u2str(usartno+1)); USND(" IRQ, ISR="); //USB_sendstr(uhex2str(USARTX->ISR)); USND("\n"); #ifdef CHECK_TMOUT static uint32_t tmout[USARTNUM] = {0}; #endif if(USARTX->ISR & USART_ISR_RXNE){ // RX not emty - receive next char #ifdef CHECK_TMOUT if(tmout[usartno] && Tms >= tmout[usartno]){ // set overflow flag bufovr[usartno] = 1; idatalen[usartno][rbufno[usartno]] = 0; } tmout[usartno] = Tms + TIMEOUT_MS; if(!tmout[usartno]) tmout[usartno] = 1; // prevent 0 #endif // read RDR clears flag uint8_t rb = USARTX->RDR; //USND("RB="); USB_sendstr(uhex2str(rb)); USND("\n"); if(idatalen[usartno][rbufno[usartno]] < UARTBUFSZI){ // put next char into buf rbuf[usartno][rbufno[usartno]][idatalen[usartno][rbufno[usartno]]++] = rb; if(rb == '\n'){ // got newline - line ready //USND("Newline\n"); linerdy[usartno] = 1; dlen[usartno] = idatalen[usartno][rbufno[usartno]]; recvdata[usartno] = rbuf[usartno][rbufno[usartno]]; // prepare other buffer rbufno[usartno] = !rbufno[usartno]; idatalen[usartno][rbufno[usartno]] = 0; #ifdef CHECK_TMOUT // clear timeout at line end tmout[usartno] = 0; #endif } }else{ // buffer overrun bufovr[usartno] = 1; idatalen[usartno][rbufno[usartno]] = 0; #ifdef CHECK_TMOUT tmout[usartno] = 0; #endif } } } void usart1_isr(){ usart_IRQ(0); } void usart2_isr(){ usart_IRQ(1); } // work with USART3 only @ boards that have it #ifdef USART3 void usart3_4_isr(){ usart_IRQ(2); } #endif