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/**
* Lets imagine that we have board with LIS3LV02DL accelerometer on channel #1
* and MAX1236 ADC, TMP75 thermometer on channel #2.
*
* NOTE: I assume, that you have datasheets on all this stuff.
*
* NOTE: Also, I assume, that you know how to I2C works.
*
* In order from simplicity to complexity:
* TMP75
* MAX1236
* LIS3LV02DL
*
* Project splitted to separate source files for each device.
*
* Data from sensors we will be read from different thread sleeping different
* amount of time.
*/
#include "ch.h"
#include "hal.h"
#include "i2c_pns.h"
#include "lis3.h"
/*
* Red LEDs blinker thread, times are in milliseconds.
*/
static WORKING_AREA(BlinkWA, 128);
static msg_t Blink(void *arg) {
(void)arg;
while (TRUE) {
palClearPad(IOPORT3, GPIOC_LED);
chThdSleepMilliseconds(500);
palSetPad(IOPORT3, GPIOC_LED);
chThdSleepMilliseconds(500);
}
return 0;
}
/*
* Accelerometer thread
*/
static WORKING_AREA(PollAccelThreadWA, 128);
static msg_t PollAccelThread(void *arg) {
(void)arg;
systime_t time = chTimeNow();
while (TRUE) {
time += MS2ST(20);
request_acceleration_data();
chThdSleepUntil(time);
}
return 0;
}
/*
* Accelerometer thread
*/
static WORKING_AREA(PollAccelThreadWA, 128);
static msg_t PollAccelThread(void *arg) {
(void)arg;
systime_t time = chTimeNow();
while (TRUE) {
time += MS2ST(20);
request_acceleration_data();
chThdSleepUntil(time);
}
return 0;
}
/*
* Entry point, note, the main() function is already a thread in the system
* on entry.
*/
int main(void) {
halInit();
chSysInit();
chThdSleepMilliseconds(1000);
I2CInit_pns();
/* Create accelerometer thread */
chThdCreateStatic(PollAccelThreadWA,
sizeof(PollAccelThreadWA),
HIGHPRIO,
PollAccelThread,
NULL);
/* Creates the blinker thread. */
chThdCreateStatic(BlinkWA, sizeof(BlinkWA), LOWPRIO, Blink, NULL);
/* main loop that do nothing */
while (TRUE) {
chThdSleepMilliseconds(500);
}
return 0;
}
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