Interfacing the overheadLeave a comment
13. March 2014 by Peter
I bought a stack of OpenCockpits cards last monts. 3 MasterCards, 3 Display cards and a USB expantion card. My plan is to use most of them for my overhead. Up until now I have used a single Pokeys56U card; so I only had 56 inputs and no outputs. Now I have 200+ inputs and almost 120 outputs. Furthermore I have a USB servo card laying around for all the gauges.
It took me a few evenings to wire up all switches on the FWD overhead. Only a few panels are not connected. But at some point I ran out of wire, and now I have to wait a few weeks before a new shipment of dupont-wire arrives from China.
The backside is one big mess at this point. I always have the best intentions. But then the wires are so short it only can run directly, and I kinda forget to get the prototyping board – that I use for each panel group – fastened.
Annunciators are also starting to work. You can see from the picture to the right how the annunciators works on the foil. On the backside picture you can see that I have made holes for the annunciators in the foam.
But again progress was brought to a halt when I ran out of yellow LEDs. 🙂
I had doubts about the annunciators. At first I through the foil was too thick for the LEDs to shine through. But using high intensity yellow LEDs in serial connection is sufficient. For the blue/White annunciators I use super bright white LEDs. But no sharing of 5v here between two LEDs. The White LED require a higher voltage and can actually work directy on 5v. Or just with a small resistor (like 100 ohm); that should be enough. But no “2 LEDs in a serial connection” here.
Another thing I managed to squeeze in yesterday was the two altitude displays. As always when working with ProSim737 it was Fairly easy to set up – well as easy as SIOC allows. 2 variables for the encoders must be configured and 2 for the displays, and then set up in the SIOC-file.