upd readme

README.md

@@ -3,6 +3,7 @@
 An [NRF24](https://www.sparkfun.com/datasheets/Components/SMD/nRF24L01Pluss_Preliminary_Product_Specification_v1_0.pdf) driver for the [Flipper Zero](https://flipperzero.one/) device. The NRF24 is a popular line of 2.4GHz radio transceivers from Nordic Semiconductors. This library is not currently complete, but functional.
 
 Settings file (default addr.txt) format:<br><br>
+
 Rate: 0/1/2 - rate in Mbps (=0.25/1/2)<br>
 Ch: 0..125 - default channel          <br>
 ESB: 0/1 (1 - Enhanced ShockBurst)    <br>
@@ -31,10 +32,16 @@ Long press OK - view addresses.<br>
 <br>
 <img src="https://raw.githubusercontent.com/vad7/nrf24scan/master/Screenshot-3.png">
 <br>
+Decode the Packet Control Field:
+<br>
 <img src="https://raw.githubusercontent.com/vad7/nrf24scan/master/Screenshot-4.png">
 <br>
+<img src="https://raw.githubusercontent.com/vad7/nrf24scan/master/Screenshot-5.png">
+<br>
+1 - pipe #
+2 - Payload length (for valide packet must be 1..20 hex)
+3 - PID (2 bit) + NO_ACK (1 bit)
 <br>
-
 ## PinOut from from NoComp/Frog
 <img src="https://media.discordapp.net/attachments/937479784726949900/994495234618687509/unknown.png?width=567&height=634">