Encoders and backwards wires

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1

Hi. I had a 42x19mm wheel encoder working a few days ago. I wired up the second one and it stopped working. I noticed that I had somehow swapped the VCC and GND lines so I corrected the problem but they still don’t work. Is it bad that I had the VCC and GND lines swapped? Did I break my encoders? I can see with a digital camera that the IR emitters still work. I’m hoping that I’m just doing something else dumb but I’ve checked the connections a few times and checked my code as well. I have a simple loop and I spin the wheels manually:

int main()
{
  unsigned int bat;
  unsigned int motors = 0;

  svp_set_mode(SVP_MODE_ENCODERS);

  bat = read_battery_millivolts_svp();
  print_long(bat);
  delay_ms(2000);

  while(1)
  {
    lcd_goto_xy(0,0);
    print_long(svp_get_counts_ab());
    print(" ");

    lcd_goto_xy(4,0);
    print_long(svp_get_counts_cd());
    print(" ");

    delay_ms(50);
  }
}
2

Hello.

Unfortunately, your encoders were likely permanently damaged by reversing the power. If you want to try again, please email us with a reference to this thread and your order information, and we might be able to offer you a discount on some replacements.

- Ben

3

ok. Thanks. That’s a bummer. I wonder how often this happens to people. I’ve been plugging it into my Orangutan so many times that I was bound to get careless and swap the wires on accident.