Update README documentations

README.md

@@ -2,6 +2,39 @@
 
 MQTT gateway for [robocar simulator](https://github.com/tawnkramer/gym-donkeycar)
 
+## Usage
+
+```
+Usage of ./rc-simulator:
+  -debug
+        Debug logs
+  -events-topic-frame string
+        Mqtt topic to events gateway frames, use MQTT_TOPIC_FRAME if args not set
+  -events-topic-steering string
+        Mqtt topic to events gateway steering, use MQTT_TOPIC_STEERING if args not set
+  -events-topic-throttle string
+        Mqtt topic to events gateway throttle, use MQTT_TOPIC_THROTTLE if args not set
+  -mqtt-broker string
+        Broker Uri, use MQTT_BROKER env if arg not set (default "tcp://diabolo.local:1883")
+  -mqtt-client-id string
+        Mqtt client id, use MQTT_CLIENT_ID env if args not set (default "robocar-simulator")
+  -mqtt-password string
+        Broker Password, MQTT_PASSWORD env if args not set (default "satanas")
+  -mqtt-qos int
+        Qos to pusblish message, use MQTT_QOS env if arg not set
+  -mqtt-retain
+        Retain mqtt message, if not set, true if MQTT_RETAIN env variable is set
+  -mqtt-username string
+        Broker Username, use MQTT_USERNAME env if arg not set (default "satanas")
+  -simulator-address string
+        Simulator address (default "127.0.0.1:9091")
+  -topic-steering-ctrl string
+        Mqtt topic to send steering instructions, use MQTT_TOPIC_STEERING_CTRL if args not set
+  -topic-throttle-ctrl string
+        Mqtt topic to send throttle instructions, use MQTT_TOPIC_THROTTLE_CTRL if args not set
+
+```
+
 ## Docker
 
 To build images, run: