Newbie and Bayangtoys

Hi,

I haven't yet purchased the Devo 7e or the NRF24L01, but I'm close. I would be primarily using it with a Bayangtoys X7 and X9. I have a couple of newbie questions that are holding be back.

1) Bayangtoys isn't supported in the release yet, correct? I need to use a nightly build? Is there a timeline for it to make it into a release?
2) How are special functions activated in flight, like flip, headless, return?
3) Is Bayangtoys the name of the protocol selected in a new model config or is it something else?
4) How do I change rates? The X9 has a low medium and height at a button press. Is there something similar with the Devo 7e deviation?

Thanks that's it for starters.

Reply to my own thread for other newbies.

1) nightly
2) Best way to figure this out is to Google the code turn in for bayang support. In the code it declares the various channel mapping. Then you need to map the channel to a switch or button. Here is an example of mapping TRIMLV+ to flip. In the model.ini

[channel6]
template=simple
[mixer]
src=Virt1
dest=Ch6
curvetype=expo
points=0,0

[virtchan1]
template=complex
[mixer]
src=Ch6
dest=Virt1
switch=Virt1
scalar=125
curvetype=expo
points=0,0

[trim1]
src=Virt1
pos=TRIMLV+
step=193
value=-100,0,0

3) Bayang

4) This is trickier. Some models have a rate channel that the transmitter must send to enable higher rates in the quad (CX-10 blue). Some models do rates all in the controller by limiting the swing of the sticks (Bayang) Here is an example of increased rate on the AIL channel for Bayang. FMODE1 is the slower rate with a default scaler of 100, were FMODE0 has a higher scaler of 125.

[channel1]
template=complex
[mixer]
src=AIL
dest=Ch1
scalar=125
curvetype=expo
points=50,50
[mixer]
src=AIL
dest=Ch1
switch=FMODE1
curvetype=expo
points=0,0

The X9 is my favorite toy quad. Stock transmitter is pretty terrible. Flies wonderfully under Deviation control. They also seem to hold up quite well. I keep thinking I've finally worn out some motors, but a few new props bring them back to life.

A few other folks have commented about using scale greater than 100 with other models so I think an explication is appropriate. Don't know how to solve the issue of finding info on the site so I'll just leave this here. I've seen mixed success with wikis on other projects...

Protocols derived from V202 (which includes most of the nRF protocols) reach their maximum control values based on full scale 100 . Anything over that does not result in more command range at the aircraft (e.g. more angle of rotation). Higher scales will feel snappier at the sticks (at 125 you'll reach full control deflection at 80% stick travel), but won't get any more angle out of the quad. An alternative is to use 100 scale and negative expo to get the responsiveness you prefer. Probably not much difference in feel between the two methods.

OK, now I'm confused. How does 100 scale and negative expo == 125 scale. I though expo was just the curve but did not effect the max and min absolute value. After reading your comment a few more times, maybe you are saying that its about other feel. The expo gives more attack?

Are you saying that anything above 100 is a waste of battery?

I'm not sure your statement "Anything over that does not result in more command range at the aircraft (e.g. more angle of rotation). " holds true for the X9. I see increased yaw. When I hover and spin then hit the FMODE I can see the yaw rate increase and decrease.

For giggles here were my theories on scale 125
* the 25 over 100 came from utilizing the trim for additional dynamic range
* I thought maybe it was based off 255 total (0xFF) were that would be -127 to 0 to +127 and then rounding to make more sense

I'm confused as well. My expectation is that the flight controller will limit the bank angle as hexfet says. However, I don't expect the sticks to control bank angle, but rate of change of the bank angle. So a rate of 125 won't give you more bank, but will get you to the maximum bank faster. Not just that you reach the maximum bank at 80% stick, but that full stick will roll to the maximum bank 25% faster than it would with a 100 rate. Or going the other way, a rate of 50 will roll at half the speed of a rate of 100.

I only have one v202 craft, and don't generally set rates over 100 unless the controls are really sluggish at 100 - like the throttle on the 200SR and the rudder on the v363 (which uses the V202 protocol). Both of those responded as expected to a rates over 100 - more lift from the 200SR (DSM protocol) and a much better yaw rate on the v363.

jboehm wrote: OK, now I'm confused. How does 100 scale and negative expo == 125 scale. I though expo was just the curve but did not effect the max and min absolute value. After reading your comment a few more times, maybe you are saying that its about other feel. The expo gives more attack?

It's the other way around. Anything over 100 is the same as 100 for these protocols/quads.

What happens is the final output of the channel mixer is made available to the protocol. Every protocol has to map that value to the data format of the protocol. For V202 and its descendants, the mapping takes a channel value of 100 to be the maximum value the protocol supports. Anything over that doesn't change the data being sent to the aircraft (because it's already at its max value). Protocols that support dyntrim are a bit more complicated but behave the same.

I looked at one of the hobby protocols once and found it mapped 100 to something less than 2000us, I guess to leave some headroom.

(coders note: The channel value in the code is scaled by 100)

jboehm wrote: Are you saying that anything above 100 is a waste of battery?

Won't affect battery in any case.

mwm wrote: I don't expect the sticks to control bank angle, but rate of change of the bank angle. So a rate of 125 won't give you more bank, but will get you to the maximum bank faster. Not just that you reach the maximum bank at 80% stick, but that full stick will roll to the maximum bank 25% faster than it would with a 100 rate. Or going the other way, a rate of 50 will roll at half the speed of a rate of 100..

The stick (technically the channel value) commands a target angle to the flight controller, and the flight controller determines the rate of rotation to reach the commanded angle. On hobby flight controllers the rate is determined by the PID settings - likely the toys have a similar algorithm.

In acro/rate mode the stick commands the rotation rate, and the angle is not limited at all.