Protocol Stacks

Probably would be more consistent/informative, if you would reset all the trims...

Your logs show the maximum range to be 0x000 to 0x3ef, so I've changed the protocol code to match.

using the 0x3ef max with my 2801Pro Rx:
2801 protocol: center = 2.0msec with +/- 0.5msec throw
2601 protocol: center = 1.2mec min=1.5 and max=1.8, so this is definitely wrong

using the value of 0x190 that I got from renatopub:
2801 protocol: center = 1.7msec with +/- 0.2msec throw

I found a spec that at 100% I should expect:
center=1.5msec with +/-0.4msec throw

So, I must have something wrong in the protocol since it isn't possible for me to achieve those values with the signals I'm sending.

wuselfuzz wrote:

FDR wrote: Probably would be more consistent/informative, if you would reset all the trims...

Didn't pay attention to those, just did some quick dumps while rushing to work. I'll do some more investigation later.

I'm interested in that, because all the four trim values are different in your logs, and I don't know if the trim value is reflected in the channel value too, or it is sent only separated.

I would like to see a channel value at min/max and mid stick with zero/min and maxed trims. (That's 9 combinations... )

Ok, I figured it out. I misunderstood renatopub's logs. In the wk2801 protocol, byte 13 is the sign bit.
when the channel is at 0, the value is 0. a value of 0x190 is either +/-100% where '+/-' is set by the relevant bit in byte 13

PhracturedBlue wrote: Ok, I figured it out. I misunderstood renatopub's logs. In the wk2801 protocol, byte 13 is the sign bit.
when the channel is at 0, the value is 0. a value of 0x190 is either +/-100% where '+/-' is set by the relevant bit in byte 13

Was that 0x190 with travel adjust maxed out or is that just the 100% ?
It will be interesting to compare the max values with the WK2402, which has no such travel adjustment...

FDR wrote: Was that 0x190 with travel adjust maxed out or is that just the 100% ?
It will be interesting to compare the max values with the WK2402, which has no such travel adjustment...

That is 100%. I was able to get the pulsewidth to 2.5msec with the RX 2801 which would be 250%
The firmware is currently only capable of driving +/-100% though.

We'll likely need to see the servo PW and packet data together on the 2402 for a channel sweep with and without trims as FDR mentioned to figure out what is actually going on.

PhracturedBlue wrote: The firmware is currently only capable of driving +/-100% though.

...and I guess that is not even the real 100%, because on the CB100 I barely could see the servos move, and the max throttle couldn't lift off the heli.

FDR wrote:

PhracturedBlue wrote: The firmware is currently only capable of driving +/-100% though.

...and I guess that is not even the real 100%, because on the CB100 I barely could see the servos move, and the max throttle couldn't lift off the heli.

Yes that is what we're talking about.
I have a fix for the 2801 that gets it to a real 100%. The code I checked in for the 2401 MAY get you there too, but we'll need to wait for wuselfuzz's data to see where we stand.

Sorry, it's my english...

I would like to say that "it is not even close to the real 100%"...

FDR wrote: Sorry, it's my english...

I would like to say that "it is not even close to the real 100%"...

With the fix I checked in an hour ago that is still true?

wusselfuzz,
there is no need to send all channels at the moment. i already have the mapping. what I need to see for a single channel is the zero, min, max with the trims zeroed, and zero/min/max with the trim maxed out. We should probably collect the same with the trim at full-min as well so we can see how sign is handled.

I would like to see both the data packet and the servo Pulse-width at these points.

I don't care about reverse (as long as we have servo pulsewidth we can figure that out)

PhracturedBlue wrote:

FDR wrote: Sorry, it's my english...

I would like to say that "it is not even close to the real 100%"...

With the fix I checked in an hour ago that is still true?

I don't know, I'm still at work, and I'm not sure I will be able to check that this evening. I spent too much time with it, and my wife got across me...

FDR wrote:

PhracturedBlue wrote:

FDR wrote: Sorry, it's my english...

I would like to say that "it is not even close to the real 100%"...

With the fix I checked in an hour ago that is still true?

I don't know, I'm still at work, and I'm not sure I will be able to check that this evening. I spent too much time with it, and my wife got across me...

I know the feeling
Anyhow, the new code does increase the range substantially for the 2401 protocol. Whether it is right or not, I do not know.

wuselfuzz wrote:

Throttle 50%, Throttle trim 100%:
df 00 2f ff a6 5f 40 c8 ff 93 86 62 a0 62 34 38 

Throttle 50%, Throttle trim 0%:
df 00 8f ff a6 00 40 c8 ff 91 86 62 40 02 49 6b

Can you check these again?
The 1st looks like 100% throttle, 0% trim
The 2nd looks like 25% throttle, 0% trim

Is it possible there is some CCPM mixing going on here, and we're not getting linear throttle control?

Edit: Rudder is probably the best channel to look at for a heli Rx I guess.

PhracturedBlue wrote: Is it possible there is some CCPM mixing going on here, and we're not getting linear throttle control?

The WK2402 does't have mixing.

PhracturedBlue wrote: Edit: Rudder is probably the best channel to look at for a heli Rx I guess.

Not really...
Even the older models have headhold gyro, which effects the rx's rudder output...

FDR wrote:

PhracturedBlue wrote: Is it possible there is some CCPM mixing going on here, and we're not getting linear throttle control?

The WK2402 does't have mixing.

PhracturedBlue wrote: Edit: Rudder is probably the best channel to look at for a heli Rx I guess.

Not really...
Even the older models have headhold gyro, which effects the rx's rudder output...

Right...4-channel doesn't have pitch control... . But the 4channel does have heading hold? how do you control it? That would need to be a 5th channel (even if it is not proportional) right?