mirror of
https://github.com/eddyem/stm32samples.git
synced 2025-12-06 10:45:11 +03:00
115 lines
3.7 KiB
C
115 lines
3.7 KiB
C
/*
|
|
* This file is part of the canbus4bta project.
|
|
* Copyright 2023 Edward V. Emelianov <edward.emelianoff@gmail.com>.
|
|
*
|
|
* 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 3 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, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <stm32f3.h>
|
|
#include "hardware.h"
|
|
#include "flash.h"
|
|
#include "usart.h"
|
|
#include <string.h>
|
|
|
|
static volatile int idatalen = 0; // received data line length (including '\n')
|
|
|
|
static volatile int linerdy = 0, // received data ready
|
|
dlen = 0, // length of data (including '\n') in current buffer
|
|
bufovr = 0; // input buffer overfull
|
|
|
|
static volatile int rbufno = 0; // current rbuf number
|
|
static char rbuf[2][UARTBUFSZ]; // receive buffers
|
|
static volatile char *recvdata = NULL;
|
|
|
|
/**
|
|
* return length of received data (without trailing zero)
|
|
*/
|
|
int usart_getline(char **line){
|
|
if(bufovr){
|
|
bufovr = 0;
|
|
linerdy = 0;
|
|
return 0;
|
|
}
|
|
if(!linerdy) return 0;
|
|
*line = (char*)recvdata;
|
|
linerdy = 0;
|
|
return dlen;
|
|
}
|
|
|
|
void usart_putchar(const char ch){
|
|
while(!(USART1->ISR & USART_ISR_TXE));
|
|
USART1->TDR = ch;
|
|
}
|
|
void usart_sendn(const char *str, int L){
|
|
if(!str) return;
|
|
for(int i = 0; i < L; ++i){
|
|
usart_putchar(str[i]);
|
|
}
|
|
}
|
|
void usart_send(const char *str){
|
|
if(!str) return;
|
|
int L = 0;
|
|
const char *ptr = str;
|
|
while(*ptr++) ++L;
|
|
usart_sendn(str, L);
|
|
}
|
|
|
|
// turn off USART1 and deinit GPIO
|
|
void usart_deinit(){
|
|
USART1->ICR = 0xffffffff;
|
|
USART1->CR1 = 0;
|
|
RCC->APB2ENR &= ~RCC_APB2ENR_USART1EN;
|
|
GPIOA->AFR[1] = GPIOA->AFR[1] & ~(GPIO_AFRH_AFRH1 | GPIO_AFRH_AFRH2);
|
|
GPIOA->MODER = GPIOA->MODER & ~(GPIO_MODER_MODER9 | GPIO_MODER_MODER10);
|
|
}
|
|
|
|
// USART1: PA10(Rx, pullup), PA9(Tx); USART1 = AF7 @PA9/10;
|
|
void usart_setup(){
|
|
GPIOA->MODER = (GPIOA->MODER & ~(GPIO_MODER_MODER9 | GPIO_MODER_MODER10)) |
|
|
MODER_AF(9) | MODER_AF(10);
|
|
GPIOA->AFR[1] = (GPIOA->AFR[1] & ~(GPIO_AFRH_AFRH1 | GPIO_AFRH_AFRH2)) |
|
|
AFRf(7, 9) | AFRf(7, 10);
|
|
RCC->APB2ENR |= RCC_APB2ENR_USART1EN;
|
|
USART1->ICR = 0xffffffff; // clear all flags
|
|
USART1->BRR = SysFreq / the_conf.usartspeed;
|
|
USART1->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(!(USART1->ISR & USART_ISR_TC)){if(--tmout == 0) break;} // polling idle frame Transmission
|
|
USART1->ICR = 0xffffffff; // clear all flags again
|
|
NVIC_SetPriority(USART1_IRQn, 0);
|
|
NVIC_EnableIRQ(USART1_IRQn);
|
|
}
|
|
|
|
void usart1_exti25_isr(){
|
|
if(USART1->ISR & USART_ISR_RXNE){ // RX not emty - receive next char
|
|
// read RDR clears flag
|
|
uint8_t rb = USART1->RDR;
|
|
if(idatalen < UARTBUFSZ){ // put next char into buf
|
|
rbuf[rbufno][idatalen++] = rb;
|
|
if(rb == '\n'){ // got newline - line ready
|
|
linerdy = 1;
|
|
dlen = idatalen;
|
|
recvdata = rbuf[rbufno];
|
|
recvdata[dlen-1] = 0;
|
|
// prepare other buffer
|
|
rbufno = !rbufno;
|
|
idatalen = 0;
|
|
}
|
|
}else{ // buffer overrun
|
|
bufovr = 1;
|
|
idatalen = 0;
|
|
}
|
|
}
|
|
}
|