/* 
glcd_primitives.c
based on Debian Slug C program to draw primitive structures on a 
graphic display controlled by a PIC i2c slave
headers modified for Sweex

------------------------------------------------------------

usage :-  type the following arguments after the program name
eg for a rectangle - glcd_primitives 81 2 100 30 110 40 1 1

arguments -
argv[1] = PIC address (0xA0 on PIC is 80 on Linux master, 0xA2 is 81)

- then send these bytes to the PIC -
argv[2] values
1 line(x1 y1 x2 y2 color(0/1))
2 rect(x1 y1 x2 y2 fill(0/1) color(0/1)
3 bar(x1 y1 x2 y2 width color(0/1) - - - fails, why?
4 circle(x1 y1 x2 y2 color(0/1))
5 text(x, y, textptr, size, color(0/1)) - later
6 pixel (x y color(0/1))
7 wipe all screen (color(0/1))

*/



#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/i2c.h>


int i2c; 
unsigned char tx_buf[8];    /* bytes to send */
int address;   /* i2c bus address */
int rc;

int main(int argc, char** argv)
{
if (argc != 9)   /* report error if we are not getting just 8 inputs after the program name */
{
printf("Error. usage: %s i2c_chip_address command arg3 arg4 arg5 arg6 arg7 arg8\n", argv[0]);           
}

address  = atoi(argv[1]);  // i2c decimal address

// the write command sends the contents of txbuf[]
tx_buf[0] = atoi(argv[2]); // command
tx_buf[1] = atoi(argv[3]);
tx_buf[2] = atoi(argv[4]);
tx_buf[3] = atoi(argv[5]);
tx_buf[4] = atoi(argv[6]); 
tx_buf[5] = atoi(argv[7]); 
tx_buf[6] = atoi(argv[8]); 


printf("address=%u\ncommand=%u arg3=%u arg4=%u arg5=%u arg6=%u arg7=%u arg8=%u\n\n", address, tx_buf[0], tx_buf[1], tx_buf[2], tx_buf[3], tx_buf[4], tx_buf[5], tx_buf[6]);


//-----------------------------------------------------------send the bytes 
i2c = open("/dev/i2c/0",O_RDWR); /* open the device dev/i2c/0 */

rc=ioctl(i2c,I2C_SLAVE,address); /* set the i2c chip address */
write(i2c,tx_buf,7);   /* we send the first 7 bytes from tx_buf[]*/
usleep(10);

i2c = close(i2c);

}