SX1268官方驱动（包含sx1278）

The aim of this project is to show an example of the endpoint LoRaWAN stack implementation. This project has 3 active branches in place. The master branch which provides the latest released source code (v4.4.2), the develop branch which provides the current source code development status to be released next (Milestone 4.4.3) and the feature/5.0.0 branch which provides a preview of the current source code development status for LoRaWAN Specification v1.1 specification.(Milestone 5.0.0) The master branch implementation is based on LoRaWAN Specification v1.0.3 and LoRaWAN Regional Parameters v1.0.3revA specifications. ClassA, ClassB and ClassC end-device classes are fully implemented. The develop branch implementation is based on LoRaWAN Specification v1.0.3 and LoRaWAN Regional Parameters v1.0.3revA specifications. ClassA, ClassB and ClassC end-device classes are fully implemented. The feature/5.0.0 branch implementation is based on LoRaWAN Specification v1.1 and LoRaWAN Regional Parameters v1.1rB specifications. ClassA, ClassB and ClassC end-device classes are fully implemented. This project also provides SX1272/73, SX1276/77/78/79 and SX1261/2 radio drivers. For each currently supported platform example applications are provided. LoRaMac/classA: ClassA end-device example application. LoRaMac/classB: ClassB end-device example application. LoRaMac/classC: ClassC end-device example application. LoRaMac/fuota-test-01: FUOTA test scenario 01 end-device example application. (Based on provided application common packages) LoRaMac/periodic-uplink-lpp: ClassA/B/C end-device example application. Periodically uplinks a frame using the Cayenne LPP protocol. (Based on provided application common packages) ping-pong: Point to point RF link example application. rx-sensi: Example application useful to measure the radio sensitivity level using an RF generator. tx-cw: Example application to show how to generate an RF Continuous Wave transmission. Note: Each LoRaWAN app