/* 
    PIC_i2c_send_data_to_to_plot_ram.c
    Send data from master to graphic display on PIC
    (8 command numbers followed by data read from master's file)
    ------------------------------------------------------------

  usage :-  type the following arguments after the program name
  eg ./PIC_i2c_send_data_to_to_plot 81 file 0 0 50 1 1 0 0 0 0

arguments -
  1 = PIC address (0xA0 on PIC is 80 on Linux master, 0xA2 is 81)
  2 = spare for file name?
  3 = number in master's data file to start reading (list_start)
  
  - send these to PIC -
  4 = pic_command[0] = PIC display starting point on x axis
  5 = pic_command[1] = number of data points sent to be displayed
  6 = pic_command[2] = 1 - wipe this data area  before plot, 0 - leave it for overwrite
  7 = pic_command[3] = 1 - we WILL plot some data points, 0 - might just switch lines etc (later)
  8 = pic_command[4] = 1 - clear screen, 0 leave it alone
  9 = pic_command[5] = 0 free
 10 = pic_command[6] = 0 free
 11 = pic_command[7] = 0 free
 
e.g.
 ./PIC_i2c_send_data_to_to_plot_ram 81 file x 22 0 1 0 0 x x x
 means ->            at x = 23, wipe local just that point, do not plot, do not clear screen
 
 - now send data values for x/y points -
 
*/

#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <unistd.h>									
#include <linux/i2c-dev.h>
#define I2C_SLAVE	0x0703	/* Change slave address	*/

  int i2c; 
  int PicData[8];             /* integers sent by PIC to master*/
  unsigned char tx_buf[100];    /* bytes to send */
  unsigned char rx_buf[8];    /* received bytes */
  unsigned long address;   /* i2c bus address */
int numbers[100];
int i, j, list_start;
int rc; //~??

int main(int argc, char** argv)
 {
 if (argc != 12)   /* report error if we are not getting just 11 inputs after the program name */
 {
  printf("Error. usage: %s i2c_chip_address then 10 data items\n", argv[0]);           
 }

       address = atoi(argv[1]); /* i2c decimal address is the first number after the program name */
           //? = atoi(argv[2]); //use for data series file name ?
    list_start = atoi(argv[3]); // point in master's data file to start reading
    
// tx_buf[0-7] are PIC commands[0-7] that come before the data stream
tx_buf[0] = atoi(argv[4]); // starting display x value for this data series
tx_buf[1] = atoi(argv[5]); //  number of points to read from file and for PIC to plot
tx_buf[2] = atoi(argv[6]); // 1 - to wipe new data area before plot, 0 - add new points on top of old
tx_buf[3] = atoi(argv[7]); // 1 - to plot some points, 0 - address ports etc later?
tx_buf[4] = atoi(argv[8]); // 1 - wipe whole screen, 0 keep old data on screen
tx_buf[5] = atoi(argv[9]); // 0 - free
tx_buf[6] = atoi(argv[10]); // 0 - free
tx_buf[7] = atoi(argv[11]); // 0 - free


  
  //--------------------------------------------read data points from file starting at point l
FILE *file_ptr;

file_ptr  = fopen("/var/www/ramdisk/AD.txt", "r");
//file_ptr  = fopen("/data/plot_data/plot.txt", "r");
if(file_ptr != NULL)
{
printf("i2c address %Lu \n",address);
printf("file opened.\n");
for ( i = 0; !feof(file_ptr); i++ )
		fscanf( file_ptr, "%d", &numbers[i] );
printf("total numbers found	: %d\n", i);
//-------------------------------------------------------------------data now all in numbers[]


for( j = 0 ; j < tx_buf[1] ; j++)
{
tx_buf[j+8] = numbers[j+list_start];//first 8 tx_buf values are commands - numbers follow them
}
fclose(file_ptr);
}
else
{ printf("unable to open file.\n"); return 1;}


printf("We are sending stream - :\n");
for( j = 0 ; j < (8+tx_buf[1]) ; j++)
{
printf("tx_buf[%u] = %d \n",j , tx_buf[j]); // print the numbers we are sending
}


printf("liststart=%u xstart=%u number=%u wipe=%u plot=%u clear=%u\n", list_start, tx_buf[0], tx_buf[1], tx_buf[2], tx_buf[3], tx_buf[4]);

  
  //-----------------------------------------------------------------get lo byte 
 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,(8 + tx_buf[1]));   /* we send bytes 8 commands + data stream> */
  usleep(10);
  
  
  
//  read(i2c,rx_buf,1);    /* rx_buf(0) now contains 2 data byte from PIC */
// usleep(10);
//  PicData[1] = rx_buf[0];
//  printf("lo byte %d \n", PicData[1]);

  //-----------------------------------------------------------------get hi byte 
//  tx_buf[0] = tx_buf[0] + 1;     /* increment x to get hi byte*/
//  write(i2c,tx_buf,6);   /* we send data again with x incremented */
// usleep(10);
//  read(i2c,rx_buf,1);    /* rx_buf(0) now contains 1 data byte from PIC */
//  usleep(10);
//  PicData[2] = rx_buf[0];
// printf("hi byte %d \n", PicData[2]);


  i2c = close(i2c);
  
// printf("double byte rebuilt %d \n", PicData[1] + 256*PicData[2]);
    
}
// NB x on the display show value sent + 1