Hello, I am trying to communicate a PCB with the launchpad LAUNCHXL2-TMS57012 through I2C. The code is simple, the launchpad has just to receive and plot what it receives; it is connecter to the PC and with Labview, I see the results. I have tried the communication with an Arduino and it works correctly. With the launchpad, I am not haveing communication. My question is, in Arduino I am using 2 pull-up resistors for the I2C communication; the launchpad seems to be yet pulled up, is it correct or should I use pull-up resistors?
The code I am using is:
/* Include Files */ #include "sys_common.h" /* USER CODE BEGIN (1) */ #include "i2c.h" /* USER CODE END */ /** @fn void main(void) * @brief Application main function * @note This function is empty by default. * * This function is called after startup. * The user can use this function to implement the application. */ /* USER CODE BEGIN (2) */ #define DATA_COUNT 8 #define Slave_Address 0x50 //uint8_t TX_Data_Master[10] = { 0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17,0x18,0x19}; //uint8_t RX_Data_Master[10] = { 0 }; //uint8_t TX_Data_Slave[10] = { 0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,0x29}; uint8_t RX_Data_Slave[8] = { 0 }; /* USER CODE END */ void main(void) { /* USER CODE BEGIN (3) */ int repeat = 0; /////////////////////////////////////////////////////////////// // Slave Receiver Functionality // /////////////////////////////////////////////////////////////// /* I2C Init as per GUI * Mode = Slave - Receiver * baud rate = 100KHz * Count = 10 * Bit Count = 8bit */ i2cInit(); /* Configure own address so that master can use it as slave address */ i2cSetOwnAdd(i2cREG1, Slave_Address); /* Set direction to receiver */ /* Note: Optional - It is done in Init */ i2cSetDirection(i2cREG1, I2C_RECEIVER); for(repeat = 0; repeat < 2; repeat++) { /* Configure Data count */ /* Note: Optional - It is done in Init, unless user want to change */ i2cSetCount(i2cREG1, DATA_COUNT); /* Tranmit DATA_COUNT number of data in Polling mode */ i2cReceive(i2cREG1, DATA_COUNT, RX_Data_Slave); /* Wait until Bus Busy is cleared */ while(i2cIsBusBusy(i2cREG1) == true); /* Wait until Stop is detected */ while(i2cIsStopDetected(i2cREG1) == 0); /* Clear the Stop condition */ i2cClearSCD(i2cREG1); } fprintf("%c", RX_Data_Slave); while(1); }
Meanwhile, the code which is working, used with Arduino is:
#include <Wire.h> uint8_t data; int nByte = 0; byte lectura[4]; unsigned long valor = 0; void setup() { Wire.begin(0x50); // join i2c bus with address #4 Wire.onReceive(receiveEvent); // register event Serial.begin(9600); // start serial for output } void loop() { delay(100); } // function that executes whenever data is received from master // this function is registered as an event, see setup() void receiveEvent(int howMany) { while (Wire.available() > 0){ // loop through all but the last data = Wire.read(); // receive byte as a character lectura[nByte]=data; nByte++; if(nByte % 4 == 0){ nByte = 0; valor = (unsigned long)lectura[3] + ((unsigned long)lectura[2]<<8) + ((unsigned long)lectura[1]<<16) + ((unsigned long)lectura[0]<<24); Serial.println(valor); } } }