libjvs sample

// Include the header and declare the I/O unit's handle pointer.
#include "libjvs/jvs.h"

static JVS_IO* jvs_io;

// Opening the JVS communication and getting the handle for the first I/O unit.
  if(!jvs_setup(jvs_port_name))
    return 0;
  if(jvs_io_count() < 1) // Check if we have at least 1 I/O unit.
    return 0;

  jvs_io = jvs_io_get(1); // Get handle for I/O unit 1.
//..........

// Closing the JVS communication.
  jvs_shutdown();
//..........

// Typical per-frame update function.
  if(!jvs_io_update(jvs_io->node, jvs_io)) // Update the I/O unit handle structure.
    return 0;
  if(!jvs_io->sw.has) // Check that the I/O unit has player input switches
    return 0;
  if(jvs_io->sw.buttons < 10) // Check that the I/O unit gives each player at least 10 switches (1 lever + 4 buttons + start + service)
    return 0;

  int j = 0;
  if(jvs_io->sw.data[j] & 0x80) {
    // ADD CODE: Handle test button
  }
  j++;
  for(int i = 0; i < jvs_io->sw.players; i++) {
    for(int l = 0; l < 10; l++) {
      if(l >= jvs_io->sw.buttons)
        break;
      if(jvs_io->sw.data[j + (l >> 3)] & (0x80 >> (l & 7))) {
        // ADD CODE: Handle switch l from player i
      }
    }
    j += (jvs_io->sw.buttons + 7) >> 3;
  }

  if(jvs_io->coin.has) {
    for(int i = 0; i < jvs_io->coin.slots; i++) {
      if(jvs_io->coin.count[i] & 0xC000) // Coin slot is not functional
        continue;
      // ADD CODE: Add (jvs_io->coin.count[i] & 0x3FFF) coins

      jvs_io->coin.subtract[i] = jvs_io->coin.count[i] & 0x3FFF; // Remove coins that were processed.
    }
  }
//..........