FlashROM interface with Embedded board

Hi All,

I am having an embedded SBC(master) and slave a 8051 based RF module having 32kbs of Internal ROM. I am having SPI bus to access that internal ROM.When i am sending some data from my master to slave using SPI bus, i am able see some data on MOSI line and after that data, i need to get some response from the slave.I am not confident that data is written properly on 00,01,02,03 address of flash ROM.I have added the code for your reference, please let me know whats wrong i am doing.

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <sys/ioctl.h>
#include <linux/types.h>
#include <linux/ioctl.h>
#include <linux/spi/spidev.h>

void run_test(int fd)
{
	int size,l,size1;
	unsigned char buf[100];

	printf("\nrun test 1\n");

	for(l=0;l<=32;l++)
	{
		size1 = snprintf(buf,100,"AC");
		write(fd,(char *)buf,sizeof(size1));

		printf("\n%x\n",buf);
	
		size1 = snprintf(buf,100,"53");
		write(fd,(char *)buf,sizeof(size1));

		printf("\n%x\n",buf);

		size1 = snprintf(buf,100,"AA");
		write(fd,(char *)buf,sizeof(size1));

		printf("\n%x\n",buf);
		usleep(4.5);
	
		size1 = snprintf(buf,100,"55");
		write(fd,(char *)buf,sizeof(size1));	

		printf("All the 4 bytes are sucessfully written\n");

		read(fd,(char *)buf,sizeof(size1));
		printf("\n\n%x\n\n",buf);

		if(strcmp(buf, "53") == 0)
		{
			printf("successfull!\n");
		} else {
			printf("failed.\n");
		}
	}
}

/*	size = snprintf(buf, 100, "Invalid data       \n");

	read_test(fd, 0, buf, size);
	buf[size] = 0;
	print_hex(buf, size);

	size = snprintf(buf, 100, "Hello world!");

	printf("Writing   \"%s\"\n", buf);


	write_test(fd, 0, buf, size);
	snprintf(buf, 100, "Invalid data       \n");

	// Give the EEPROM enough time to commit
	usleep(5000);

	read_test(fd, 0, buf, size);
	buf[size] = 0;
	print_hex(buf, size);

	write_disable(fd);

	if(strcmp(buf, "Hello world!") == 0)
	{
		printf("SPI EEPROM Read/Write test successfull!\n");
	} else {
		printf("SPI EEPROM Read/Write failed.\n");
	}*/

#define SPI_MSB 0
#define SPI_LSB 1


int initialize_spi(const char *dev, char mode, char msb, char bpw, __u32 max_speed)
{
	char fd;
	fd = open(dev, O_RDWR);

	if(fd < 0)
	{
		perror("open");
		return -1;
	}

	if(ioctl(fd, SPI_IOC_WR_MODE, &mode))
	{
		perror("SPI_IOC_WR_MODE");
		return -1;
	}
	if(ioctl(fd, SPI_IOC_WR_LSB_FIRST, &msb))
	{
		perror("SPI_IOC_WR_LSB_FIRST");
		return -1;
	}
	if(ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bpw))
	{
		perror("SPI_IOC_WR_BITS_PER_WORD");
		return -1;
	}
	if(ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &max_speed))
	{
		perror("SPI_IOC_WR_MAX_SPEED_HZ");
		return -1;
	}
	return fd;
}

int main(int argc, char **argv)
{
	const char *dev = "/dev/spidev1.2";
	int fd, opt;

	while ((opt = getopt(argc, argv, "01")) != -1)
	{
		switch(opt)
		{
			case '0':
				dev = "/dev/spidev1.0";
				break;
			case '1':
				dev = "/dev/spidev1.2";
				break;
			default:
				fprintf(stderr, "%s: Pass -0 for McSPI3.CS0 test, or -1 for McSPI3.CS1 test\n", argv[0]);
				exit(-1);
		}
	}

	if(optind < argc)
	{
		printf("Opening \"%s\" for SPI communication\n", argv[optind]);
		fd = initialize_spi(argv[optind], SPI_MODE_0, SPI_MSB, 8, 800000);
	} else {
		printf("Opening \"%s\" for SPI communication\n", dev);
		fd = initialize_spi(dev, SPI_MODE_0, SPI_MSB, 8, 800000);
	}

	if(fd < 0)
	{
		fprintf(stderr, "initialize_spi failed\n");
		return -1;
	}

/*	{
		struct at25080a_status_register reg;
		get_status(fd, &reg);
		printf("Status is: 0x%02hhx\n", (*((char *)&reg) & 0xff));
	}*/	

	run_test(fd);

	close(fd);
	return 0;
}

Regards,
Ravi