Files
stm32samples/G0:G070,G0B1/g0b1/main.c
Edward Emelianov 71d30dd19a rename G0:G070
2026-03-01 23:12:53 +03:00

87 lines
2.7 KiB
C

/*
* This file is part of the blink 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 "stm32g0.h"
#define KEY_PORT GPIOC
#define KEY_PIN (1<<13)
#define LED_PORT GPIOC
#define LED_PIN (1<<6)
#define KEY_PRESSED() (pin_read(KEY_PORT, KEY_PIN) == 1)
#define LED_ON() do{pin_set(LED_PORT, LED_PIN);}while(0)
#define LED_OFF() do{pin_clear(LED_PORT, LED_PIN);}while(0)
// KEY (intpullup->0) - PC13
// LED - PC6
static volatile uint32_t blink_ctr = 0;
/* Called when systick fires */
void sys_tick_handler(void){
++blink_ctr;
}
/*
* Set up timer to fire every x milliseconds
*/
static void systick_setup(uint32_t xms){ // xms < 2098!!!
blink_ctr = 0;
static uint32_t curms = 0;
if(curms == xms) return;
// 8MHz - HCLK/8
// this function also clears counter so it starts right away
SysTick_Config(8000 * xms); // arg should be < 0xffffff, so ms should be < 2098
curms = xms;
}
static void gpio_setup(void){
RCC->IOPENR = RCC_IOPENR_GPIOCEN; // enable PC
// set PC8 as opendrain output, PC0 is pullup input, other as default (AIN)
GPIOC->MODER = (0xffffffff & ~(GPIO_MODER_MODE6 | GPIO_MODER_MODE13)) | GPIO_MODER_MODER6_O; // GPIO_MODER_MODER13_I == 0
GPIOC->PUPDR = GPIO_PUPDR13_PD; // pull down
}
static const uint32_t L[] = {125,100,125,100,125,200, 350,100,350,100,350,200, 125,100,125,100,125, 1000};
int main(void){
StartHSE();
gpio_setup();
systick_setup(500);
uint32_t M = 0;
int pressed = 0;
/* Do nothing in main loop */
while (1){
if(KEY_PRESSED()){ // key pressed - 'sos'
pressed = 1;
systick_setup(L[M]);
if(M & 1) LED_OFF();
else LED_ON();
if(++M == 18) M = 0;
while(blink_ctr == 0);
}else{ // key not pressed - blink with period of 1s
if(pressed){
M = 0;
pressed = 0;
systick_setup(500);
}
if(blink_ctr & 1) LED_ON();
else LED_OFF();
}
}
}