Crazyflie 2.0 Expansion board driver prototype

traficlight.c

#include <stdbool.h>

#include <gpio.h>
#include <exp.h>

#define RED EXP_IO1
#define ORANGE EXP_IO2
#define GREEN EXP_IO3

static bool isInit = false;

static void traficLightInit()
{
  gpioInit(RED, GPIO_OUTPUT, GPIO_SLOW);
  gpioInit(ORANGE, GPIO_OUTPUT, GPIO_SLOW);
  gpioInit(GREEN, GPIO_OUTPUT, GPIO_SLOW);
  
  isInit = true;
}

static struct expDefine_s {
  .init = traficLightInit,
  .type = "cftlh",                      //Type written in the OW memory
  .uses = [RED, ORANGE, GREEN, NULL],   //List of pins or peripheral used
} traficlightExp;

EXP_REGISTER(traficlightExp);

static int state;

static void traficlightVariableUpdated(void* variable)
{
  if (state > 3) {
    return;
  }
  
  if (state == 0) {
    gpioSet(RED, 0);
    gpioSet(ORANGE, 0);
    gpioSet(GREEN, 0);
  } else if (state == 1) {
    gpioSet(RED, 1);
    gpioSet(ORANGE, 0);
    gpioSet(GREEN, 0);
  } else if (state == 2) {
    gpioSet(RED, 0);
    gpioSet(ORANGE, 1);
    gpioSet(GREEN, 0);
  } else if (state == 3) {
    gpioSet(RED, 0);
    gpioSet(ORANGE, 0);
    gpioSet(GREEN, 1);
  }
}

PARAM_GROUP_START_EN(E_traficlight, isInit)                               //The callbacks are enabled by isInit
PARAM_ADD(PARAM_UINT8 | PARAM_RO, present, &isInit)
PARAM_ADD_CB(PARAM_UINT8, state, &state, traficlightVariableUpdated)      //Callback when the value is written
PARAM_GROUP_END(E_traficlight)