Update README.md

README.md

@@ -1,6 +1,20 @@
 # pocsag-gateway
 
 This WIP Software aims to provide an Interface for transmitting Messages sent over AMQP via an RFM69 Transceiver.
+## Software Configuration
+Configuration works via Environment Variables or a `.env` file.
+```
+POCGW_AMQPURL=amqp://guest:guest@10.13.37.37:5672
+
+POCGW_TXBAUD=1200
+POCGW_RXBAUD=1200
+
+POCGW_TXFREQ=434230000
+POCGW_RXFREQ=434230000
+
+POCGW_FREQOFFSET=25
+```
+If TX or RX Frequency are not set or set to 0, the software will not use this mode(only-rx or only-tx). If both are set, then rx is always active until there are pages to tx.
 
 ## Pin Configuration
 | RFM pin | Pi pin