Update README.md

Author: JonasVautherin

sdk/README.md

@@ -31,10 +31,10 @@ MAVSDK-Java is mainly autogenerated from the MAVSDK [proto files](./proto), usin
 
 ### Prerequisites
 
-MAVSDK-Java is built using gradle, but `protoc-gen-mavsdk` must be in your PATH in order to auto-generate the code. It requires Python 3.6+ and can be installed using:
+MAVSDK-Java is built using gradle, but `protoc-gen-mavsdk` v1 must be in your PATH in order to auto-generate the code. It requires Python 3.6+ and can be installed using:
 
 ```sh
-pip3 install protoc-gen-mavsdk
+pip3 install "protoc-gen-mavsdk~=1.0"
 ```
 
 Make sure to add `protoc-gen-mavsdk` to your PATH!