(Solved): #include "stm32l4xx.h" /* Microcontroller information */ /* Define global variables */ static int va ...
#include "stm32l4xx.h" /* Microcontroller information */
/* Define global variables */
static int value1, value2; /*counter values */
unsigned static char run = 0; //controls if the counters are
counting
unsigned volatile char up = 0; //controls which direction the first
one is counting
unsigned static char led1, led2 = 0; //led1 == red led - represents
state of "run" variable. led2 == ylw led - represents state of "up"
variable.
void PinSetup () {
/* Configure PA1, PA2 as input pin to read the
switches */
RCC->AHB2ENR |= 0x01; /* Enable GPIOA clock
(bit 0) */
GPIOA->MODER &= ~(0x0000003C); /* General
purpose input mode */
/* Configure PB[5:3] as output pins to drive DIO
LEDs */
GPIOA->MODER &= ~(0x03FFFC00); /* Clear
PB[5:3] mode bits */
GPIOA->MODER |=
(0x01555400); /* General purpose output mode for
PB[5:3]*/
/* Configure PB4,PB3 as output pins to drive
LEDs */
RCC->AHB2ENR |= 0x02; /* Enable GPIOB clock
(bit 1) */
GPIOB->MODER &= ~(0x000003C0); /* Clear
PB4-PB3 mode bits */
GPIOB->MODER |=
(0x00000140); /* General purpose output mode*/
}
/*----------------------------------------------------------*/
/* Delay function - do nothing for about 0.05 second */
/*----------------------------------------------------------*/
void delay () {
int volatile i,j,n;
for (i=0; i<20; i++) { //outer loop
for (j=0; j<20000; j++) {
//inner loop
n = j;
//dummy operation for single-step test
} //do nothing
}
}
/*----------------------------------------------------------*/
/* Count function - increment/decrement the counters */
/*----------------------------------------------------------*/
void count() {
if(up==0){
value1++;
if(value1==6){
value1=0;
}
}else{
value1--;
if(value1==-1){
value1=5;
}
}
value2++;
if(value2==6){
value2=0;
}
GPIOA->ODR = (value1 << 5) //Write
value1 to PB[5:3]
}
/*------------------------------------------------*/
/* Main program */
/*------------------------------------------------*/
int main(void) {
PinSetup(); //Configure GPIO pins
/* Endless loop */
while (1) {
delay();
run = GPIOA->IDR &=
0x0002; //PA1 = switch, which is also the "run" value.
up = GPIOA->IDR &=
0x0004; //PA2 = switch, which is also the "UP/DOWN" value.
if(run != 0){ //A COMMON
MISTAKE! "Set" is not "1".
count();
//Never being called? Look at the assembly code, as see if "run" is
never being loaded. If not, you need to declare it
differently.
}
} /* repeat forever */
}
