diff --git a/src/energenie/drv/radio.c b/src/energenie/drv/radio.c
index af3238c..e870262 100644
--- a/src/energenie/drv/radio.c
+++ b/src/energenie/drv/radio.c
@@ -276,6 +276,25 @@
 // Send a payload of data
 //TODO: Rewrite this to use FIFOLEV and FIFOEMPTY with payloadlen=0
 //rather than PACKETSENT, as it will allow any number of repeats.
+//
+
+/* NEW DESIGN
+
+   CONFIGURE
+     set packetlen=0 (arbitrary length)
+     set fifolevel=payloadlen-1
+     set txcondition=fifolevel
+
+   TRANSMIT PAYLOAD
+     fifo burst a single payload into fifo
+
+   WAIT NEXT
+     wait for fifolev interrupt flag to be set
+
+   WAIT FINISHED
+     wait for fifoempty interrupt flag to be set
+     (wait 1 byte * bps to ensure last byte transmitted)
+*/
 
 void radio_send_payload(uint8_t* payload, uint8_t len, uint8_t repeats)
 {