AutoQuad native Graupner HoTT telemetry (update jan 2015)

[phynix]

I dosn't have a picture of my copter right now - this is happening on a big frame that is still in developement... some data if someone is interested:

flat octo, 1m diameter, 22mm cfk-tubes
x2212 motors with 11'' props (e-prop style)
ultraESC
Graupner MX20 (GR24)
bluetooth telemetry
3S/4S batteries
AQ+DIMU with hott-firmeware
power distribution and esc seperated from FC by both CFK centerplates (in total >50mm), all wires twisted, PWM lines seperated as far as possible from power-lines
(brushless Gimbal + video transmission)
2,5 kg without camera and batteries

the motor speed with this combination is unfortunately close to the resonance of the arms - so the vibrations are a little bit too high (in my opinion). But it flies well and this will be solved by the use uf bigger motors with larger props - as soon as the other problem is solved

[r0sewhite]

Just watched my CPU load indoor after removing props (no GPS fix):
- about 75-80% in disarmed state
- between 55 and 65% when motors are running, up to 75% when I trigger something like WLR, Homepoint or RTH.

I will do some more tests tomorrow to find out what affects the CPU load.

[teramax]

Guys i know this means nothing but let me tell you i fly Mennos creations on 5 rigs, one nearly a year and all together countless charges till today.
There are ESC32, UltraESC and KISS builds all on 4s.
The only difference might be that i am very economical with my builds -should mean when the esc is running also without the signal-ground wire -i skip it, DIMU telemetry out needs no ground wire -i skip it, when..... and so on.

But all this reports leave a bad feeling every flight so i realy hope this issue gets fixed some day.

ps.: i remember month ago while testing betas i found some kind of stack overflow what caused the FC to freeze. It was marked and fixed very quick. So let us hope

[DUKE40]

So the two reported cases are with more than 4 motors flat (hexa for Tilman and octo for Phynix) might be an idea to look into that direction.
I have never looked into the source code of AQ, but I know from programming for computers, that this might affect the load on the CPU.

[r0sewhite]

Duke, this is surely not the reason. Almost any of my AQ-equipped copters is an octo and I never experienced any issues.

But what I found out so far is that the HoTT telemetry adds about 20% MCU load, in armed as well as in disarmed state. I will go on finding out what eats my MCU's ressources but if I don't find the cause, I will disable HoTT telemetry.

[phynix]

I have roughly the same values for the MCU load that Tilman has - just checked. Highest value was 85 - with motors not running.

[kinderkram]

[r0sewhite]

Yes Norbert, I kept in mind that it happened after changing a parameter by tablet but phynix and teramax confirmed a load of up to 80-85%. What I said is that I need to find out what kills my headroom but if I can't find the cause, I would rather disable HoTT and have 20% more headroom.

I didn't test the regular r416 but setting TELEMETRY_HOTT to 0 leads to 20% less MCU load.

[teramax]

[aBUGSworstnightmare]