Files
42_EXT_03_42chips/module01/ex00/main.c
2025-03-06 10:26:39 +01:00

88 lines
2.5 KiB
C

#include <avr/io.h>
// stringify
#define STRINGIFY_HELPER(x) #x
#define STRINGIFY(x) STRINGIFY_HELPER(x)
// concatenate
#define CONCAT_HELPER(x, y) x ## y
#define CONCAT(x, y) CONCAT_HELPER(x, y)
// get argument
#define ARG_1(v1, v2) v1
#define ARG_2(v1, v2) v2
#define GET_PORT(args) ARG_1 args
#define GET_BIT(args) ARG_2 args
// actions on registers
#define SET(register, bit) register |= 1 << bit
#define CLEAR(register, bit) register &= ~(1 << bit)
#define TEST(register, bit) register & 1 << bit
#define TOGGLE(register, bit) register ^= 1 << bit
// actions on elements
#define SET_ELEM(elem) SET(CONCAT(PORT, GET_PORT(elem)), GET_BIT(elem))
#define CLEAR_ELEM(elem) CLEAR(CONCAT(PORT, GET_PORT(elem)), GET_BIT(elem))
#define TEST_ELEM(elem) TEST(CONCAT(PORT, GET_PORT(elem)), GET_BIT(elem))
#define TOGGLE_ELEM(elem) TOGGLE(CONCAT(PORT, GET_PORT(elem)), GET_BIT(elem))
#define MODE_OUTPUT(elem) SET(CONCAT(DDR, GET_PORT(elem)), GET_BIT(elem))
#define MODE_INPUT(elem) CLEAR(CONCAT(DDR, GET_PORT(elem)), GET_BIT(elem))
#define TOGGLE_PIN(elem) SET(CONCAT(PIN, GET_PORT(elem)), GET_BIT(elem))
#define TEST_PIN(elem) (TEST(CONCAT(PIN, GET_PORT(elem)), GET_BIT(elem)))
#define IS_PIN_SET(elem) (TEST_PIN(elem) == 0)
#define IS_PIN_CLEAR(elem) (TEST_PIN(elem) == 1)
// bits
#define D1 0
#define D2 1
#define D3 2
#define D4 4
#define SW1 2
#define SW2 4
// elements (port, bit)
#define LED1 (B, D1)
#define LED2 (B, D2)
#define LED3 (B, D3)
#define LED4 (B, D4)
#define BUTTON1 (D, SW1)
#define BUTTON2 (D, SW2)
// TIME
#define PRESCALE_VALUE 1024
#if (PRESCALE_VALUE == 1)
#define PRESCALE_SET (1 << CS10)
#elif (PRESCALE_VALUE == 8)
#define PRESCALE_SET (1 << CS11)
#elif (PRESCALE_VALUE == 64)
#define PRESCALE_SET (1 << CS10) | (1 << CS11)
#elif (PRESCALE_VALUE == 256)
#define PRESCALE_SET (1 << CS12)
#elif (PRESCALE_VALUE == 1024)
#define PRESCALE_SET (1 << CS10) | (1 << CS12)
#endif
#define TIME_MS(ms) (((F_CPU / PRESCALE_VALUE) * ms) / 1000)
// END MACROS
int main() {
MODE_OUTPUT(LED2);
CLEAR_ELEM(LED2);
TCCR1B |= (PRESCALE_SET); // set timer with prescale
// -> 16.4 : set timer with bits CS10-12, in register TCCR1B
// -> table 16-5 : prescale values
while(1) {
if (TCNT1 >= TIME_MS(500)) { // 16.11.4 : read timer with register TCNT1 (read/write allowed), that combines two 8 bits registers
TOGGLE_PIN(LED2);
TCNT1 = 0; // reset timer value, also in register TCNT1
}
}
}