Using MAX in a mix

[Allan Bennett]

Up to now I've been creating a throttle-cut function using a Special Function to override CH3:Thr, but since updating my OTX Companion to 2.3.9 and my receivers to v2.1.0 firmware I'm encountering several instances where that doesn't have any effect on the throttle channel -- at least, not in the OTX Companion simulation.

So now I'm trying to implement what a clubmate tells me is a more elegant way of achieving the same thing, by adding a "+= MAX Weight (-200%) Switch (!SG up-arrow)" to my throttle mix, and in OTX Companion simulation it works. But what worries me is that it sets the throttle to -200% with reference to the throttle stick's position, so that if the throttle stick is at zero (i.e. -100%) and SG is activated the the throttle channel goes to -300%.

Is there a better way of having a throttle-cut switch, please? And would it do my ESCs any harm to receive a -300% signal?

[David Hall 9]

One aspect of OpenTx is that there is often more than one way to mix.

My own for throttle kill is to add source Thr (could be anything), weight 0, offset -100, multiplex replace, switch of your choice etc...     

 

 

Edited By David Hall 9 on 16/07/2020 18:38:10

[Mark H75]

You raise a good point Re. companion. I have found it to be flaky with respect to simulation compared to testing the functionality on a real Tx. The last time I used it (using code 2.3.7) it was doing the inverse of what I wanted; tried it on my real Tx and worked as expected.

As David mentions, there's 1001 ways of doing things in OpenTx, with that in mind, I generally follow Painless360 and Richard Mrázek on youtube for my simple(ton) requirements.

[Allan Bennett]

As it happens, I've just found the solution! The key to it is the 'Multiplex' option in the MAX definition window: Setting it to 'REPLACE' instead of the default (which think was 'ADD' ), it replaces the value resulting from the first line of my throttle mix, so a value of -100 simply sets throttle to -100 when the cut switch is activated, irrespective of the throttle stick position.

I'm on OTX 2.3.9, and I had read somewhere that 2.3.7 was problematic. I must admit it was only today during some bench testing that I noticed that the simulation wasn't shutting the throttle for some of my models, even though they were all configured the same way in that respect. I haven't checked if it works properly on all the actual models, though I do know it's working on some that I've flown since I upgraded. But anyway I'm going to convert them all to the MAX method instead of a Special Function.

Another issue I've noticed with the simulation is on one of my models using an S8R stabilised receiver I've programmed the momentary switch SH to activate, and announce, Panic Mode. On the actual transmitter it works correctly, but as soon as I go into the simulator it makes the announcements at 5-second intervals (as programmed) with the switch 'off', and only stops if I move the switch to 'on' and then back to 'off'.

Edited By Allan Bennett on 16/07/2020 21:25:17