title: Disable the default red LED on the ACR122U
body: <p>I would like to send an APDU such that the default LED state on the ACS ACR122U card reader (without a card present) will be that no LEDs are lit.</p>
  
  <p>The documentation would indicate that such a command would be <code>FF 00 40 0c 04 00 00 00 00</code>, leaving the <code>Final LED State</code> of both Red and Green at 0 (off). However, this just flashes the light to off then back.</p>
  
  <p>This seems to be because APDUs go to the card not to the reader. However, there are Pseudo-APDUs that control the device parameters. Basically, I know it's not documented, but does anyone know if such a parameter still exists? Or some workaround?</p>
  
  <p>Thanks, Gausie.</p>