2018-11-05 13:33:03 +03:00

90 lines
3.0 KiB
C

/*
* main.c
*
* Copyright 2018 Edward V. Emelianov <eddy@sao.ru, 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 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 "stm32f1.h"
static volatile uint32_t blink_ctr = 0;
/* Called when systick fires */
void sys_tick_handler(void){
++blink_ctr;
}
// SysTick is 24 bit counter, so 16777215 - max value!!!
// After HSE is ON it works @72MHz (or remove SysTick_CTRL_CLKSOURCE_Msk @ SysTick_Config for 8MHz)
static void systick_setup(uint32_t xms){
static uint32_t curms = 0;
if(curms == xms) return;
// this function also clears counter so it starts right away
SysTick_Config(72000 * xms);
curms = xms;
}
static const uint16_t L[] = {125,100,125,100,125,200, 60,100,60,100,60,200, 125,100,125,100,125, 230};
static void gpio_setup(void){
/* Enable clocks to the GPIO subsystems (A&B) */
RCC->APB2ENR |= RCC_APB2ENR_IOPBEN | RCC_APB2ENR_IOPCEN;
/* Set leds (PB8/PB9) as opendrain output */
GPIOB->CRH = CRH(8, CNF_ODOUTPUT|MODE_SLOW) | CRH(9, CNF_ODOUTPUT|MODE_SLOW);
/* Set buttons (PC0/1) as inputs with weak pullups */
GPIOC->ODR = 3; // pullups for PC0/1
GPIOC->CRL = CRL(0, CNF_PUDINPUT|MODE_INPUT) | CRL(1, CNF_PUDINPUT|MODE_INPUT);
}
int main(){
sysreset();
StartHSE();
gpio_setup();
systick_setup(100);
uint32_t oldctr = 0xff;
pin_clear(GPIOB, 3<<8);
/* Do nothing in main loop */
while (1){
if(pin_read(GPIOC, 1) && pin_read(GPIOC, 2)){ // no buttons present - morze @ LED1 (PB9)
if(oldctr != blink_ctr){
uint32_t T = blink_ctr % 18;
systick_setup(L[T]);
if(T & 1) pin_set(GPIOB, 1<<9);
else pin_clear(GPIOB, 1<<9);
oldctr = blink_ctr;
}
}else{ // button pressed: turn ON given LED
if(pin_read(GPIOC, 1) == 0){ // PC0 pressed (button S2)
systick_setup(5);
if(blink_ctr - oldctr > 499){
pin_toggle(GPIOB, 1<<9);
oldctr = blink_ctr;
}
}else pin_set(GPIOB, 1<<9);
if(pin_read(GPIOC, 2) == 0){ // PC1 pressed (button S3)
systick_setup(1);
if(blink_ctr - oldctr > 499){
pin_toggle(GPIOB, 1<<8);
oldctr = blink_ctr;
}
}else pin_set(GPIOB, 1<<8);
}
}
}