Add submission # 3728

#3728

Author: ArduinoBot

registry.txt

@@ -6572,3 +6572,4 @@ https://github.com/littleBitsman/Asynchrony.git|Contributed|Asynchrony
 https://github.com/PU2REO/Si5351ArduinoLite.git|Contributed|PU2REO Si5351ArduinoLite
 https://github.com/Sam4uk/CRSF.git|Contributed|CRSF
 https://github.com/hpsaturn/MultiFuncShield-Library.git|Contributed|MultiFuncShield
+https://github.com/arduino-libraries/Arduino_PF1550.git|Arduino|Arduino_PF1550