/* Compile with: gcc -Wall -o lauflicht lauflicht.c expander_lib.c */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "expander_lib.h"

int main(int argc, char *argv[])
  {
  mcp23017 expander;  /* Verwaltungs-Structure */
  int data = 0x01;    /* Ausgabewert */
  int down = 0;       /* Richtungsangabe */

  expander = init_mcp23017(0x20,0,0,"/dev/i2c-1");

  while(1)
    {
    /* beide Ports identisch "bedienen" */
    write_mcp23017(expander,GPIOA,data);
    write_mcp23017(expander,GPIOB,data);

    if (data == 0x80) /* ganz links - umdrehen */
      down = 1;
    if (data == 0x01) /* ganz rechts - umdrehen */
      down = 0;

    if (down)
       data = data >> 1;
    else
       data = data << 1;
    usleep(100000); /* 100 ms Pause */
    }

  return 0;
  }