There is some confusion. On the HFP you still need at least the signal wire from each channel of the RX to the HFP. I believe the original question was can you use PPM? or a single wire connection like SBUS. We have talked about it but there are more important things on our development schedule. We just didn't see eliminating a few RX connections to be a must have. In addition, some of the bus type connections use proprietary and in some cases would require a license to use. Easy for the Chinese or a project controller but we have to consider this when integrating with other hardware.