Transponder Offset 0x0354 No Longer Working?

[ark1320]

As best as I can recall, before the recent MSFS update on 9 March I could set transponder codes by writing to offset 0x0354, e.g., ipc.writeUW(0x0354, 1234). This offset no longer seems to work (can't read or write transponder codes) after the MSFS update.  I would appreciate if someone could confirm (or not) they are seeing the same thing.

Thanks,

Al

[John Dowson]

3 hours ago, ark1320 said:

I would appreciate if someone could confirm (or not) they are seeing the same thing.

There's also a new SDK with yesterdays release, v0.11.0.0. I'll rebuild FSUIPC7 using this SDK and release later today, so may be worth checking again once thats done.

[ark1320]

9 hours ago, John Dowson said:

There's also a new SDK with yesterdays release, v0.11.0.0. I'll rebuild FSUIPC7 using this SDK and release later today, so may be worth checking again once thats done.

Hi John,

Just tried offset 0x0354 again with FSUIPC v7.06, but still can't access the transponder in a default plane. Unfortunately it seems Asobo changed something wrt the transponder unless the problem is local to my system for some reason.

Take care,

Al

[John Dowson]

Ok. I'll check when I get a chance and report to Asobo. What a/c were you using?
And, again, if it was a mod, did you try the vanilla version?

[ark1320]

1 hour ago, John Dowson said:

Ok. I'll check when I get a chance and report to Asobo. What a/c were you using?
And, again, if it was a mod, did you try the vanilla version?

John,

I have tried the C152, C172(Steam gauge), and DA-40s(NG and TDI), all with nothing in my Community folder -- so all vanilla a/c. I can set the transponder mode in these a/c via offset  0x0B46, but can't set or read the 4 digit code with offset 0x0354.

Thanks,

Al

[John Dowson]

Ok, thanks for the update. I'll take a look when I get time.

[jaxx]

I can confirm that I can no longer write the transponder code via 0x0354. But reading still works for me. (Using FSUIPC 7.06)

Edit:
Just for clarification on reading. When writing a value to 0x0354 it is written to the offset (and consecutive reads will return the value written), but it is not propagated to the sim. When reading from 0x0354 the value is only updated again from the sim when I change it from within the sim.

Edited March 11, 2021 by jaxx

[ark1320]

1 hour ago, jaxx said:

I can confirm that I can no longer write the transponder code via 0x0354. But reading still works for me. (Using FSUIPC 7.06)

Edit:
Just for clarification on reading. When writing a value to 0x0354 it is written to the offset (and consecutive reads will return the value written), but it is not propagated to the sim. When reading from 0x0354 the value is only updated again from the sim when I change it from within the sim.

That interesting. I just tried again with the the C172 (Steam gauge), and I can't write or read the transponder, even if I change the code in the sim.

Al

[John Dowson]

On 3/10/2021 at 8:50 PM, ark1320 said:

so all vanilla a/c. I can set the transponder mode in these a/c via offset  0x0B46, but can't set or read the 4 digit code with offset 0x0354.

Strange - just took a look (in the C152) and I can read ok but not update, same as for @ark1320.

I have corrected the writing to 0x0354 in the attached version (v7.0.7c) if you can both try.

FSUIPC7.exe

 

[ark1320]

5 hours ago, John Dowson said:

Strange - just took a look (in the C152) and I can read ok but not update, same as for @ark1320.

I have corrected the writing to 0x0354 in the attached version (v7.0.7c) if you can both try.

FSUIPC7.exe 594.5 kB · 0 downloads

 

John,

The good news is I can now at least get the transponder in the steam gauge C172 to respond using your new FSUIPC7.  The bad news is the value displayed in the transponder is wrong. I tried an experiment and get the following results when setting the C172 transponder using, for example.  ipc.writeUW(0x0354, 0010) which displays 0002 in the C172. 

Code Written          Code Displayed in the C172

0000                             0000

0001                             0001

0010                             0002

0100                             0064

1000                            0360

So it seems the values being written are getting scrambled somehow. I don't see anything "common" in these results.

However, values read back are apparently being interpreted as a Hex value. If I set the transponder with the mouse in the VC and then read the value with  ipc.readUW(0x0354) I get:

VC Transponder code        Value read back and displayed

0000                                               0

0001                                                1

0010                                              16

0100                                              256

1000                                              4096

Al

 

[John Dowson]

But its a BCD field - i.e. binary encoded. So, to set as, for example, 0100, write as 0x0100. When you write that as 0100, thats 0x256, so will display 256, etc.

Sorry, if thats not clear from the documentation, I will update - I'll check tomorrow....late here and time for a beer...!

[ark1320]

46 minutes ago, John Dowson said:

But its a BCD field - i.e. binary encoded. So, to set as, for example, 0100, write as 0x0100. When you write that as 0100, thats 0x256, so will display 256, etc.

Sorry, if thats not clear from the documentation, I will update - I'll check tomorrow....late here and time for a beer...!

It all works now with you latest version of FSUIPC7.  The Offset Status documentation is quite clear.  I just had forgotten it was BCD ☹️ -- sorry. Another age problem I guess. Sigh.

Thanks for the help.

Al

[John Dowson]

No worries, happens to us all...! Glad its now working, but I'm a bit mystified why I needed to make this change...the fix was to add some code back that was removed in a previous version. However, if it was previously working, I don't understand how...

Probably to do with MSFS updates - and I may have hacked-it to work via other means which no longer apply. I'll check when I get a chance.

John

[Maxpilot22]

Should have looked earlier in here, could have saved me 2 hours. Same problem, all ok with the new FSUIPC7.exe.