132 lines
4.3 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"
#include "usart.h"
static volatile uint32_t Tms = 0; // milliseconds from last reset
// Called when systick fires
void sys_tick_handler(void){
++Tms;
}
// setup
static void gpio_setup(void){
// Enable clocks to the GPIO subsystems
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(){
int L;
char *txt;
sysreset();
StartHSE();
gpio_setup();
usart_setup();
uint32_t Told = 0;
SysTick_Config(72000); // interrupt each ms
SEND("Greetings!"); newline();
pin_set(GPIOB, 3<<8); // turn off LEDs
/* Do nothing in main loop */
while (1){
if(Tms - Told > 499){ // blink LED1 every 1 second
pin_toggle(GPIOB, 1<<9);
Told = Tms;
transmit_tbuf();
}
if(usartrx()){ // usart1 received data, store in in buffer
L = usart_getline(&txt);
char _1st = txt[0];
if(L == 2 && txt[1] == '\n'){
L = 0;
switch(_1st){
case '0': // turn off LED2
SEND("LED2 off");
pin_set(GPIOB, 1<<8);
newline();
break;
case '1': // turn it on
SEND("LED2 on");
pin_clear(GPIOB, 1<<8);
newline();
break;
case 's':
case 'S':
SEND("LED2 state: ");
if(pin_read(GPIOB, 1<<8)) SEND("off");
else SEND("on");
newline();
break;
default: // help
SEND(
"'0' - turn off LED2\n"
"'1' - turn on LED2\n"
"'s' - test LED2 state\n"
);
break;
}
}
transmit_tbuf();
}
if(L){ // echo all other data
txt[L] = 0;
usart_send(txt);
transmit_tbuf();
L = 0;
}
/*
uint8_t
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);
}*/
}
}