Returns a true/false value if there's no signal on the channel?

1. Save the value of PHYRegister 0x403

2. Set the channel to the channel currently being tested

3. MaskSet PHYRegister 0x403 with mask 0xFFF8 and set with 5

4. If the "Use Hardware RSSI Value" ACI Flags flag is set

   1. Read the value of PHYRegister 0x48A, mask with 0x3F

5. Otherwise
   1. Use the saved value instead and mask with 0x3F
6. If this value is greater than 32, subtract 64 (clamps to a signed 5 bit value), this is the RSSI Power Level
7. Loop up to 100 times

   1. Read PHYRegister 0x47F, right shift by 8 and mask with 0x3F

   2. If this value is greater than 32, subtract 64 (clamps to a signed 5 bit value)
   3. If this value is less than the RSSI Power Level
      1. If the value has been less than the RSSI Power Level 20 times

         • Restore the value of PHYRegister 0x403 and return true

   4. Delay 10 uSec

8. Restore the value of PHYRegister 0x403 and return false