| Quote: Originally Posted by Daemon | | | | |
| It's a module based system with PPM signal as the input.
PPM frames are 20ms long. XPS can not send updated stick positions until the next
PPM frame comes along.
There's nothing illogical about how it works, and it can't really work any other way.
If it were tied directly to the Tx CPU then it could send updated stick positions much more frequently. | |
| | |
This is why I chuckle when I hear people gushing over how much more responsive their models feel with XPS (or any other module-based system).
The *fastest* way to get the stick positions to the servos is actually to use a good old FM/PPM receiver.
There are no processing or packetization delays -- the pulse is simply used to modulate the transmitter which produces a corresponding change in the receiver which is passed straight onto the servo.
All *any* module-based 2.4GHz system can do is add extra delays to the basic FM/PPM model.
Yes, a good module-based 2.4GHz system might just be better than a PCM system but I've never heard anyone using PCM saying "I feel more disconnected than when I used FM" so I still wonder if the difference is actually perceptible.
Ain't the placebo effect a wonderful thing :-)
The reality is that on 2.4GHz we have bandwidth to burn so the next step will doubtless be a doubling or tripling of the frame-rate -- but that won't be of much use until we have servos that can also cope with a much faster pulse-rate than the current 50Hz.
Exciting things ahead for RC :-)