FGCom compatibility of audio panel/radios

[hbeni]

Currently FGCom is linked to the first radio (i think). We could integrate the audio panel more into the FGCom:

• [x] Disconnect FGCom when selected radio fails; reenable if it comes back to live (circuit breaker tripped? just no power? radio died?) Just opened a core ticket for that: https://sourceforge.net/p/flightgear/codetickets/2256/
• [x] Switch FGCom radio when selecting another MIC button from the panel (or back to comm1 when panel fails/turned off)
• [x] Adjust FGCom speaker volume (GMA speaker-button set it to "0" or the previous value of fgcom)
• [x] Let selected MIC LED blink when FGCom PTT is active

see fgfs forum: https://forum.flightgear.org/viewtopic.php?f=32&t=33232&p=368615#p368615 see fgcom source: https://sourceforge.net/p/flightgear/flightgear/ci/next/tree/src/Network/fgcom.cxx

Properties seem to be:

• /controls/radios/comm-radio-selected (0=disabled, 1=com0, 2=com1)
• /sim/fgcom/speaker-level (0 silent, 1 full)

(Follow up from PR #180 )

[hbeni]

GMA-340 handbook says (page 3):

Speaker Output Pressing the SPKR button (12) selects aircraft radios over the cabin speaker. The speaker output is muted when a COM microphone is keyed. The GMA 340 speaker output level can be adjusted by your installing agency

So we just might ignore that or implement it so that disabling the speaker turns fgcoms speaker to "0" and turning it on sets the volume to the currently set value from fgcom.

[hbeni]

Implementation in branch issue324_FGCom-GMAPanel. I tested it locally with 2019.1.1 but for FGCom in 2020 versions the FGCom properties did change. I honored that so both versions should work.

Properties seem to be set just fine - the only question remaining is, if FGCom will pick it up correctly. We need some testers in recent FGFS versions so this can be stabilized.

Test cases (estimated time to run trough: 2 minutes):

• With activated GMA audio panel and COM1 on, it should work as usual.
• When pushing SPACE (PTT button) the LED of the selected MIC should blink shortly approx. every second to indicate active transmission.
• When pushing the COM2-MIC switch, FGCom should switch over to the COM2-frequency.
• When deactivating the GMA audio panel (pull circuit breaker, disable Avionics Switch 2, system failure of the panel) FGCom should fall back to COM1 frequency.
• When deactivating the selected radio (in this case: COM1; pull circuit breaker, disable Avionics Switch 1, system failure on COM1) it should disconnect FGComs channel.
• When reactivating GMA and COMs, all should be fine again
• Selecting COM-MIC2 and disabling COM2, FGCom should disconnect (selected radio died -> needs pilot interactions / switch over to COM1).
• Switching to the working COM1 again should reenable FGCom.
• Switching back to the dead COM2 should disconnect FGCom.
• Reenabling COM2 should bring FGCom back on frequency of COM2.

(announced it on the forums)

[hbeni]

I tested with 2019.1.1 today and basic function works. With COM1 i could connect to FGCom and disabling the radio did shut down FGCom. reenabling worked.

Further tests still pending; i currently try to build fgfs 2020.2.0

[hbeni]

Further testing revealed: the /controls/radios/comm-radio-selected property is hardwired to the code. From the aircraft perspective, it is read-only (could be set but confuses FGComs internal state).

The currently only solution i think is FGComs controls: SPACE=COM-1, CTRL+SPACE=COM-2. The thing we could do is to let the corresponding COM-MIC LED that is used, blink, so the pilot sees which Radio he transmits on and otherwise set the MIC-Buttons readonly.

Further investigation could reveal if we instead can overwrite the key bindings for FGCom. Maybe also it could be that FGCom just has the keybinding set to write the PTT and radio property, in this case we might just overwrite that code.... but where is this?

[hbeni]

but where is this?

controls.nas in fgdata: https://sourceforge.net/p/flightgear/fgdata/ci/next/tree/Nasal/controls.nas and this overwrites our preset values. It also seems that in the /controls/radios/comm-ptt propety the value of the used com has to be entered. keyboard.xml defines the trigger for when space is pressed or released (space() gets called). Can we override that so the old code doesn't trigger?

---

Edit: just tested: when setting either the /instrumentation/comm[n]/ptt to 1, then FGCom will start to transmit on that radio (controls.nas defines listeners for that). So we either

• overwrite the SPACE for the transmission to select the correct radio ptt property. This will maybe confuse users used to fgcoms behaviour.
• or add another keybinding specific to our plane (ctrl+space?). This will leave fgcomms keys and behaviour intact. However, that also prevents us from advanced GMA simulation.

@HHS81 please advise, what would you do? I would say, that the current implementation where we hilight the LED of the radio currently used for transmission is a good compromise. We cannot disable receiving messages, even when the radios are dead (thats hardwired in fgcom) anyway. Currently users might try to swith radios using the buttons however, and will fail. Maybe we disable the LED switching when pressing MIC2 or MIC3, so MIC1 always stays current (it's the default fgcom radio anyway)?

[hbeni]

(overwriting is trivial, just did it. Should we go that route, Heiko? @HHS81 )

[hbeni]

Tonight it struck me like lightning! We easily can have both. I will introduce a new realistically aircraft option and if it’s checked, i overwrite the space key. If not, default behavior is looped trough.

[hbeni]

Got it working now in the current commit.

commit 0cd66c0b85a4b693ab6c04922e1f2cf34228fb75 (HEAD -> issue324_FGCom-GMAPanel) Author: hbeni beni@hallinger.org Date: Tue Jun 2 00:02:54 2020 +0200

GMA-340 / FGCOM integration

• corrected the implementation of commit d2c1b4ea9b, that one was not eintirely correct. Current implementation is much cleaner.
  • GMA 340 / FGCom Integration can now be turned on in the c182s aircraft menu. Default is off (fgcom standard behaviour).
  • When integration is disabled, just the LEDs blink for the radio used from FGCom, when transmitting.
  • When integration is enabled, the current MIC radio is switched with the audio panel button "COM+MIC". Then pressing space and shift-space is the same, it will transmit on the selected radio. When the selected radio is dead, transmission will not occur. When the GMA Panel dies, the hardwired COM1 failsafe will activate automatically. This all was tested using 2020.2.0 / Revision: e76787fa62 using two PCs and two fgcom standalone instances for monitoring the frequencies PHNL TWR+UNICOM.

So this is ready for merge in my eyes. We probably should make an entry in the next fgfs newsletter for this...

[hbeni]

Hi @stuartbuchanan I think we missed to close this one - the code seems to be already in master. What do you think (would be good if you could confirm and close, as I'm only 99% sure)

beni@segin:~/Dokumente/FGFS/work/c182s$ git branch --contains 8dfb580
  Issue331-UpgradeRadio
  damage
  fgcom-fixNoListener
* master
  master-merged
  tyresmoke

[hbeni]

Verified, is already merged, so i close this now.