#include "bsp.h"
#include "tty.h"

int i2c_bytep;
int i2c_count;
char i2c_bytes[] = { 0x00, 0xff, 0x55, 0xaa, 0x80, 0x01 };

/* tx = NACK */
void __attribute__((interrupt))
s0tx_handler (void)
{
  p2.b = 'N';
  if (i2c_bytep == i2c_count)
    {
      u0smr4.b = 0x04;
      u0smr4.b = 0x0c;
    }
  else
    {
      u0tbw = i2c_bytes[i2c_bytep++] | 0x0100;
    }
}

/* rx = ACK */
void __attribute__((interrupt))
s0rx_handler (void)
{
  p2.b = 'A';
}

void __attribute__((interrupt))
s0ss_handler (void)
{
  p2.b = 'S';
  if (i2c_bytep)
    /* End of transmission */
    i2c_bytep = -1;
  else
    {
      /* Start of transmission */
      p2.b = 0;
      u0c1.b = 0x15;	/* enable tx, rx */
      p2.b = 1;
      u0smr4.b = 0x00;
      p2.b = 2;
      u0tbw = i2c_bytes[0] | 0x0100;
      p2.b = 3;

      i2c_bytep = 1;
    }
}

main()
{
  int i;

  pd2.b = 0xff;
  p2.b = 0x55;

  pd6.b = 0x0c;
  pur2.b = 0x01;
  wait_ms (3);

  for (i=0; i<50; i++)
    {
      p6.b = 0xff;
      p6.b = 0x00;
    }
  p2.b = 0xC1;
  pd6.b = 0x00;
  wait_ms (1);
  p2.b = 0x0f;

  // Set up UART0 for serial output for testing.

  u0brg = 99;  /* 20 mhz / 200 khz / 8*/

  u0mr.b = 0x02;	/* UART, 8N1 */
  u0c0.b = 0xb0;	/* LSB first, CMOS, buffered, f1, CRD, NCH? UFORM? !CKPOL */
  u0c1.b = 0x10;	/* disable tx, rx */

  u0smr.b = 0x01;
  u0smr2.b = 0x00;
  u0smr3.b = 0xe2;
  u0smr4.b = 0x70; /* commands */

  ps0.b = 0x0c;
  psl0.b = 0x02;

  /* Interrupts */
  ifsr = 0xc0;
  s0tic = 0x05;
  s0ric = 0x05;
  bcn0ic = 0x05;
  asm("fset I");

  p2.b = 0xAA;
  wait_ms (1);
  while (1)
    {
      wait_ms (1);

      i2c_bytep = 0;
      i2c_count = 6;

      p2.b = 0x81;
      /* Generate start condition */
      u0smr4.b = 0x71;
      u0smr4.b = 0x09;

      /* wait for interrupts to cycle through the whole data stream.  */
      while (i2c_bytep != -1)
	p2.b = u0smr4.b;

      p2.b = 0x84;
    }

}