Slave Device

Overview of basic functions for I2C communication with Feelix.

Download the library with example codes here. Version 1.8 and later.

Define the address of the slave and index. The index should correspond to the position in the slaves array in the master code uint8_t slaves[] = { SLAVE_0_ADDRESS }

#define SLAVE_0_ADDRESS 0x70
#define SLAVE_INDEX     0

Initialization

Initialize Feelix as slave device after Feelix.init() in void setup()

/* initialize Feelix as slave device*/
feelix.init_I2C_Slave(
    SLAVE_0_ADDRESS,        //address of slave device
    SLAVE_INDEX,            //index of slave defined in initializer master device (uint8_t slaves[])
    &callback_I2C_Request,  //callback that fires when master requests data
    DEBUG,                  //(optional)
                            // bool debug (set to false before production)
    callbackArr,            //(optional)
                            // array with callback functions (functionPtr)
    callbackLength);        //(optional)
                            // size of array

Initialize Feelix as slave device after Feelix.init() in void setup()

/* initialize Feelix as slave device*/
feelix.init_I2C_Master(
    slaves[],               //index of slave defined in initializer master device (uint8_t slaves[])
    CLOCK_SPEED::SLOW_MODE, //Clock frequency 
    &callback_I2C_Request,  //callback that fires when master requests data
    DEBUG,                  //(optional)
                            // bool debug (set to false before production)
    callbackArr,            //(optional)
                            // array with callback functions (functionPtr)
    callbackLength);        //(optional)
                            // size of array

Reply to master

Reply with device parameters on master request

/* callback that fires when the master requests device parameters*/
void callback_I2C_Request() {

    /* return device parameters 
     * function takes masterCallbackIndex as argument
     */
    feelix.slave.returnDeviceParameters(0);
    feelix.toggleLED(STM32_LED_ORANGE);
}

Receive data from master

Create callback functions to receive data from master

/* callback that fires when the master sends float */
void callBack_receiveFloat() {
    variable_target = feelix.slave.receiveFloat();
}

/* callback that fires when the master sends int */
void callBack_receiveInt() {
    data = feelix.slave.receiveInt();
}

/* callback that fires when the master sends byte */
void callBack_receiveByte() {
    activeEffect = feelix.slave.receiveByte();
}

/* callback that fires when the master sends char array */
char arr[6]; /* allocation required */

void callBack_receiveCharArray() {
    feelix.slave.receiveCharArray(arr, sizeof(arr));
}

Create callback array to store all callbacks. The master can use the index of the callback function in the array to trigger a specific callback on the slave side.

/* array to store callback functions */
const functionPtr callbackArr[] = { 
    callBack_receiveFloat,    //slaveCallbackIndex 0
    callBack_receiveInt,      //slaveCallbackIndex 1
    callBack_receiveByte,     //slaveCallbackIndex 2
    callBack_receiveCharArray //slaveCallbackIndex 3
};
/* calculate length of array (do not change) */
uint8_t callbackLength = sizeof(callbackArr)/sizeof(functionPtr);