diff --git a/libnfc/drivers/pn53x_usb.c b/libnfc/drivers/pn53x_usb.c
index db1a15b..4d32867 100644
--- a/libnfc/drivers/pn53x_usb.c
+++ b/libnfc/drivers/pn53x_usb.c
@@ -586,7 +586,9 @@ pn53x_usb_configure (nfc_device_t * pnd, const nfc_device_option_t ndo, const bo
   switch (DRIVER_DATA (pnd)->model) {
     case ASK_LOGO:
       if (NDO_ACTIVATE_FIELD == ndo) {
-        // Switch on/off progressive field according to ACTIVATE_FIELD option
+        // Switch on/off progressive field
+        // and switch on/off LED2
+        // according to ACTIVATE_FIELD option
         DBG ("Switch progressive field %s", bEnable ? "On" : "Off");
         if (!pn53x_write_register (pnd, SFR_P3, _BV(P31) | _BV (P34), bEnable ? _BV (P34) : _BV (P31)))
           return false;
@@ -594,6 +596,7 @@ pn53x_usb_configure (nfc_device_t * pnd, const nfc_device_option_t ndo, const bo
       break;
     case SCM_SCL3711:
       if (NDO_ACTIVATE_FIELD == ndo) {
+        // Switch on/off LED according to ACTIVATE_FIELD option
         if (!pn53x_write_register (pnd, SFR_P3, _BV (P32), bEnable ? 0 : _BV (P32)))
           return false;
       }