PM FCU Problem

[imported_darrens]

I have 4 Phidget encoder\decoders connected to my Airbus FCU to alter the SPD, HDG, ALT and V/S.

http://www.phidgetsusa.com/cat/viewp...=4100&SKU=1052

There is a small problem I have at the moment which I cannot resolve.

When I come out of Managed Mode, the display correctly switches to show the HDG\SPD. When I turn the encoder\decoder to alter the HDG\SPD the value does not continue from what is diplayed but defaults from another value. For example, when I switch out of Managed Mode, the HDG may be showing 270. Let's suppose I want to turn right to 290. I turn the encoder\decoder but the value will change to, let's say 140 and then I have to quickly turn the encoder\decoder to 290 to stop the a/c banking to the left to pick up 140. It only happens when I use the encoder\decoder.

What appears to be happening is that the FS2Phidget software (v3.12) is not reading the current PM value and taking it from there.

Is there a solution?

Best wishes,

Darren Sugden

[alandyer]

Darren,

What offset did you assign to the encoder ?
What step value are you using ?

Regards,
Alan.

[imported_darrens]

For Speed I am using Offset 5406 Length 2
For Heading I am using Offset 5408 Length 2
Both have a Step Value of 1

Regards,

Darren

[alandyer]

Darren,

What is the value for heading offset ( 5408 ) before you attempt to change with encoder ?

There are two ways to check this out:
- Use FSEdit screen on FS2Phidget
- Assign 5408 to line on Dummy tab and check out value in FS Value.

What ini file did you create offset 5408 in ?
Assuming you have set that up correctly.

Regards,
Alan.

[imported_darrens]

Hello, Alan. Thank you for your reply.
I created a Dummy Tab but I was unable to enter any values in it - don't know why. Remember, I am not using an IO card from Phidgets, just the built in encoder:

http://www.phidgetsusa.com/cat/view...y=4100&SKU=1052

I started up the sim and the aircraft was sitting on the runway with a heading already showing in the FCU of 230 degrees. I used the PM FCU software i.e. the mouse to dial in a SPD of 250 knots. Note that I have not turned the Phidget encoder yet.

I then turned the encoder to dial in a SPD of 260 knots (still sitting on the runway) but it changed immediately to 183 knots before I could increase it to 260 knots. Before I did that I checked what FS value the Phidget was reporting (clicking on the 'Edit FS Variables' tab) and it showed the FS Value being 183. I have attached a screenshot to show you.

When I used the encoder to alter the heading from 230 to 240 degrees (still on the runway), it changed immediately to a value of 209 degrees before I could increase it. The FS Value showed an initial value of 209 when I checked it using the 'Edit FS Variables tab.

Now, everything will work fine now until I put the aircraft into Managed Mode. Coming out of Managed Mode into Selected Mode and using the encoder to alter HDG and SPD creates the problem again.

What appears to be happening is that when the PM FCU is doing all the calculations in Managed Mode (or initial start-up as described above) it is not telling the FS2Phidgets software (or FS2Phidgets software is not able to read the changes occurring to SPD and HDG). I have quickly done a test and aircraft and put it into managed mode. Coming out of Managed Mode the heading was showing 220 degrees. I then turned the encoder to the right to increase the HDG to 230 degrees but it defaulted to 210 degrees before any increases were made.

I don't know whether it is a PM problem or a FS2Phidets problem.

Regards,

Darren

[alandyer]

Darren,

I had 2 requests - you need to work with me on those.

(1) I asked you for your set up of offset 5408. That's where reported problem lies. You gave me screen shot of 5406 - the Airspeed.

(2) I asked for the 5408 value BEFORE (not after) you touched the encoder.

Here is what I want you to do:
- When you come out of managed mode.
- Look at 5408 value using FSEdit.
- Let me now what that is.
BEFORE (English), VORN (German), VOOR (Dutch), PRE (Latin), PHAMBI (Zulu), DON'T LIKE TOUCH THE %%^#&* ENCODER, DUDE (Californian).

We want to observe what is happening inside that PM controlled offset without any input from the encoder.

At which point, we'll be on our way to discovering whether this a PM or FS2Phidget problem.

Technically, the encoder card is an IO card.

Regards,
Alan.

[imported_darrens]

Thank you Alan for your patience on this.

1) Lined up on RWY 21 at EGNJ
2) FCU showing HDG 207
3) Offset 5408 is showing a value of 0 (see attached screenshot - it is grayed out)
4) I take off and go into Managed Mode (still haven't touched the encoder)
5) Aircraft turns to its first interesection (GOLES)
6) I come out of Managed Mode and HDG is showing 288 on the FCU
7) I check the 5408 value and it is still showing 0
When I turn the encoder HDG resets to 0 before moving on.

I hope this is the information that you wanted

[alandyer]

Darren,

You have 5408 offset defined correctly.
So we can rule that out.

During time frame from your item (1) to (7) offset 5408 is managed by Project Magenta software.
Bet if you look at offset 04E2 (Heading - read) you will see correct value visible on your screen.
We cannot write to offset 04E2 (which is a good thing ).

PM uses TWO offsets to manage many objects.
One for reads and one for writes.

PM does this to ensure reliability and performance.
It is considered good software engineering and is entirely appropriate in this scenario.
( I don't get any kick-back from PM. Promise ! )
( Just know a good product when I see one)

There's also a good chance PM will provide direct Phidget encoder support from within their software for FCU functions in the future.

Looks like FS2Phidget is working as designed.
- it reads the value from the offset (zero).
- increments or decrements the value by the step value you specified.
- writes new value back to offset.

I can modify design by adding additional Read-Offset assignment to encoder calibration screen.

Could you play with the two offsets and confirm that the read offset (04E2) ALWAYS has correct heading value ? I'm almost sure it will.
I'm Boeing 737 driver - don't have Airbus FCU.

Regards,
Alan.

[imported_darrens]

Thank you once again for your swift reply.

Both offsets 5408 and 04E2 were showing the same value throughout the flight.

The problem appears that when the aircraft goes into Managed Mode the software is not detecting any heading changes that occurs in that mode. It's last memory of heading is when it was in Selected Mode.

I have just done another flight and here are the results:

I was lined up on the runway with the FCU showing a heading of 207 degrees. Both offsets 5408 and 04E2 were showing a value of 0 degrees.

Immediately after take off the a/c was put into Managed Mode to follow the flight plan set up in the MCDU. Both offsets are still reading 0 degrees. After a couple of minutes I decided to go into Selected Mode. The FCU reported a heading of 282 degrees - the heading to the first waypoint. Both offsets are still showing a value of zero degrees.

I then turned the encoder to tell the a/c I wanted to turn to a heading of 310 degrees. The heading first defaulted to 0 degrees before turning to the new heading of 310 degrees.

Both offsets were now showing a value of 310.

I then went back into Managed Mode to allow the a/c to pick up the flight plan and pass the first waypoint. The a/c turned to a heading of 240 degrees.

Both offsets were still showing a value of 310.

The a/c, which is still in Managed Mode, passed the first waypoint and turned to a heading of 217 degrees to pick up the second waypoint.

Both offsets were still showing a value of 310.

I then went into Selected Mode and used the encoder to turn the a\c to 190 degrees. It defaulted to 310 degrees before making the change.

Both offsets were now showing a value of 190.

What appears to be the case is that it is remembering the last heading when in Selected Mode but is not able to see any changes that may have occurred once the a/c went into Managed Mode.

Phew!

I hope that makes sense.

Is this a problem that can be solved at your end or must I bounce this one to Enrico?

All the very best,

Darren

[alandyer]

Darren,

If neither of those two offsets contains an accurate heading when FCU emerges from managed mode I'm not sure what I can do.

Is there not perhaps another offset ? What about 07CC ?

Regards,
Alan.