linknlink emotion modbus

mb.c

// cc -Wall mb.c $(pkg-config --cflags --libs libmodbus)
//
#include <stdio.h>
#include <stdlib.h>
#include <modbus.h>

int main(int argc, char **argv) {
  modbus_t *mb;
  uint16_t motion, no_motion;

  if (argc != 2) {
    fprintf(stderr, "usage: %s IP_ADDRESS\n", argv[0]);
    exit(2);
  }

  mb = modbus_new_tcp(argv[1], 502);
  if (modbus_connect(mb) == -1) {
    fprintf(stderr, "error connecting\n");
    exit(1);
  }

  modbus_read_registers(mb, 802, 1, &motion);
  modbus_read_registers(mb, 832, 1, &no_motion);

  modbus_close(mb);
  modbus_free(mb);

  printf("motion = %#x\n", motion);
  printf("no motion = %#x\n", no_motion);
}