No PDC answer using Prosim737 expert help needed

Hello Guys,

we need help to get a working PDC with the new datalink system implemented in Prosim737.
The Prosim devolpers need to know in which format the clearance is send.

I can send a PDC on my FMC
Its logged on hoppie´s ACARS
Vpilot ATC is processing request and sends back PDC
The Problem is: Its only displayed on hoppie´s webpage not on the FMCs.
and I cant not accept the Clearance
So its pretty much useless at the moment.

Answer Developer:

" Hi,

PDC is sent as telex, so far so good. But communication after that is done as CPDLC messages, and to get those you need to be logged on.
But basic problem is the very simple Hoppie protocol used. plain text. I did some investigations and PDC related messages have different formats (maybe related to network used) and makes really difficult to parse them automatically without log on.

From the logic side, ProSim is correct, but from the virtual network system we don’t know how they do their stuff… or how different clients handle these requests.
Technically, PDC messages are of specific types (FSM,CLD,CDA, etc) and are not CPDLC messages, but Hoppie network is using them as CPDLC.
Also, message is sent in plain text and different formats… the acronym is in there but is simply not enough to automatically parse the message and process it properly.

Thus the dead end about it.

Note that PDC was implemented expecting a telex answer.
Problem is that we have no accurate way of linking pdc request with answer. Like we have for pure CPDLC messages. It is like calling someone on the land line phone and the person then return the call from the cell phone. You cannot correlate these calls l.
If this was properly documented we could implement it in a way it would work but seen different answer formats which makes it difficult. Other vendors have intermediate server to handle this and have a pseudo relation between the telex PDC and the CPDLC answer. We work with pure hoppie server without any hack in between. And that’s how it will be.
I understand your frustration, but If you can find specific VATSIM pdc info regarding how they format the pdc answer we can make it work for VATSIM. We need to differentiate the PDC answer and mark it as such so we can create the proper message in ProSim.
But again, if different clients are used, answers can be formatted differently."

I’d say, talk to the developers of FlyByWire. They have implemented working PDC/CPDLC functionality for their Airbus product.

Otherwise check out the the GitHub page of “EasyCPDLC”.