I2C interfacing with Zybo Z7020

[Niranjana]

Hi ,

I am trying to establish I2c protocol between the FPGA board and an external device(a TI board) in which the FPGA board acts as master and sends the data.

I created the Zynq processing IP and enabled I2C1 for the corresponding pins. I exported the .xsa file to XIlinx Vitis and coded by referring the example given in the examples directory for i2c_master_polled_example.c.

The code is as follows.

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/*
 * helloworld.c: simple test application
 *
 * This application configures UART 16550 to baud rate 9600.
 * PS7 UART (Zynq) is not initialized by this application, since
 * bootrom/bsp configures it to baud rate 115200
 *
 * ------------------------------------------------
 * | UART TYPE   BAUD RATE                        |
 * ------------------------------------------------
 *   uartns550   9600
 *   uartlite    Configurable only in HW design
 *   ps7_uart    115200 (configured by bootrom/bsp)
 */

#include "xparameters.h"
#include "xiicps.h"
#include "xil_printf.h"

#define IIC_DEVICE_ID		XPAR_XIICPS_0_DEVICE_ID

#define IIC_SLAVE_ADDR		0x55
#define IIC_SCLK_RATE		100000

XIicPs IicPsInstance;			/* Instance of the IIC Device */

static void i2c_init();
static void datasend();


static void i2c_init()
{
	XIicPs_Config *Config;
	/*
		 * Initialize the IIC driver so that it's ready to use
		 * Look up the configuration in the config table, then initialize it.
		 */
	Config = XIicPs_LookupConfig(IIC_DEVICE_ID);
	XIicPs_CfgInitialize(&IicPsInstance, Config, Config->BaseAddress);
	/*
	 * Perform a self-test.
	 */
	XIicPs_SelfTest(&IicPsInstance);
	XIicPs_SetSClk(&IicPsInstance, IIC_SCLK_RATE);

}

static void datasend()
{
	unsigned char sendbuffer[3] = {0xA,0xB,0xC};
	//uint8_t myReadBuffer[3] = {};

	//xil_printf("the value at receive buffer before datasend is %X\n",rcvbuffer[0]);


	XIicPs_MasterSendPolled(&IicPsInstance ,sendbuffer, 3 , IIC_SLAVE_ADDR );

	xil_printf("Transferred successfully\n");

}

int main()
{
	i2c_init();
	datasend();

    return 0;
}

I am unable to receive the data in the slave.. what am I missing?