FS2004 Can't capture button press

[lmhariano]

I'm trying to make a gauge that, when the trim button is pressed, a variable is changed but the trim is not moved. So, this is what I did:

<Element>
        <Keys>
            <On Event="ELEV_TRIM_DN">
                (A:Sim On Ground,bool) ! if{ (>K:ELEV_TRIM_UP)
                (L:FBW_ref, number) 0.5 + (>L:FBW_ref, number) }
            </On>
        </Keys>
</Element>

<Element>
        <Keys>
            <On Event="ELEV_TRIM_UP">
                (A:Sim On Ground,bool) ! if{ (>K:ELEV_TRIM_DN)
                (L:FBW_ref, number) 0.5 - (>L:FBW_ref, number) }
            </On>
        </Keys>
</Element>

Since I found that the gauge did not react as expected, I tried changing the event for PROP_PITCH_INCR/_DECR:

<Element>
        <Keys>
            <On Event="PROP_PITCH_INCR">
                (A:Sim On Ground,bool) ! if{ (L:FBW_ref, number) 0.5 + (>L:FBW_ref, number) }
            </On>
        </Keys>
</Element>

<Element>
        <Keys>
            <On Event="PROP_PITCH_DECR">
                (A:Sim On Ground,bool) ! if{ (L:FBW_ref, number) 0.5 - (>L:FBW_ref, number) }
            </On>
        </Keys>
</Element>

I removed the opposite trim movement line, since it was no longer required. But still does not react. Did I do something wrong?

 

[Luka]

Remove the Element tag and use the ELEVATOR_TRIM_SET to prevent jamming with TRIM_UP/DN endless loop.

<Gauge>
...
<Keys>
    <On Event="ELEV_TRIM_DN">
        (A:Sim On Ground,bool) ! if{ 0 (>K:ELEVATOR_TRIM_SET)
        (L:FBW_ref, number) 0.5 + (>L:FBW_ref, number) }
    </On>
    <On Event="ELEV_TRIM_UP">
        (A:Sim On Ground,bool) ! if{ 0 (>K:ELEVATOR_TRIM_SET)
        (L:FBW_ref, number) 0.5 - (>L:FBW_ref, number) }
    </On>
</Keys>
...
</Gauge>

 

[Anthony31]

As Luka says, the <Keys> section works much like the <Mouse> section so you should only use one <Keys> section.

Check also to see if it still works when you are in the exterior view. I have found in the past that <Keys> don't work unless you are in the virtual cockpit view although I may be mistaken. I only tried it once a few years ago and when it didn't work for me I changed to using a C++ gauge to handle events.

 

[lmhariano]

Thanks, Luka and Anthony. Since it won't do anything visual, I already have this gauge installed into [Vcockpit01] (same place where Posky/TDS/SkySpirit leaves their XML gauge animations). I guess there should be no problem.

Regarding the possible infinite loop, thanks for pointing out this possibility. Now I have another 2 more questions:

1) I want to leave the trim untouched while in flight. Thus, Luka's code would be changed into this:

<Gauge>
...
<Keys>
    <On Event="ELEV_TRIM_DN">
        (A:Sim On Ground,bool) ! if{
        (L:FBW_ref, number) 0.5 + (>L:FBW_ref, number) }
    </On>
    <On Event="ELEV_TRIM_UP">
        (A:Sim On Ground,bool) ! if{
        (L:FBW_ref, number) 0.5 - (>L:FBW_ref, number) }
    </On>
</Keys>
...
</Gauge>

With this code, if I press the trim button inflight, would I be moving the trim?

2) Is it there any equivalence between (>K:ELEV_TRIM_DN) and this?

(A:ELEVATOR TRIM INDICATOR, number) X - (>K:ELEVATOR_TRIM_SET)

I mean, what would be the value of X? This taking into account that both ELEVATOR_TRIM_INDICATOR and ELEVATOR_TRIM_SET go between -16k and +16k.

 

[taguilo]

1) I want to leave the trim untouched while in flight.

What you actually need is "cancel" the UP and DOWN events by triggering the opposite one in each case.
And you must use a flag variable to avoid entering an endless loop :

<Keys>
<On Event="ELEV_TRIM_DN">
    (L:TrimDownByCode,bool) !
    if{        
         (A:Sim On Ground,bool) !
         if{  (>K:ELEV_TRIM_UP)
              (L:FBW_ref, number) 0.5 + (>L:FBW_ref, number)
              1 (>L:TrimUpByCode,bool)
            }
         }
    0 (>L:TrimDownByCode,bool)
</On>

<On Event="ELEV_TRIM_UP">
    (L:TrimUpByCode,bool) !
    if{
         (A:Sim On Ground,bool) !
         if{  (>K:ELEV_TRIM_DN)
              (L:FBW_ref, number) 0.5 - (>L:FBW_ref, number) }
              1 (>L:TrimDownByCode,bool)
            }
       }
     0 (>L:TrimUpByCode,bool)
</On>
</Keys>

Making

(A:ELEVATOR TRIM INDICATOR, number) X - (>K:ELEVATOR_TRIM_SET)

is always possible but won't be as exact -in this case - as triggering the opposite event.

Tom

 

[lmhariano]

¡Muchas gracias, Tom! I'm currently using PROP_PITCH as the trigger event, it works beautifully. After I finish coding everything, I'll try to change trigger event to ELEVATOR_TRIM.