It has been a while since I have added my pressure sensor but this is what I remember:
Export your current USER files to usb stick and put them on your computer The .SFG file is the sensor definition file. Open this file with Windows notepad or any text editor.
I added a hydraulic pressure sender to my system. It has an output of approx 500psi/volt with an output range of approx. .5 to 4.5V (0 to 2000psi). So, paste this to the bottom of your sensor .SFG file.
Adjust the C_x0 and C_x1values to match your transducer. The industry standard y=C1*X + C0. If you tell me your sensor output I can help with the calibration.
Add one more sensor definition for the second transducer. Change the name=HYD PRESS to whatever you want to name it.
Save this file as any "unique name".SFG and put it on a usb mem stick. Import the new .SFG file to your Skyview system. Then configure the new sensor as any other. chose the widget, size and location, etc.
This should work - the only thing you need to be aware of is when updating SV firmware you will have to re-import your custom SFG file after upgrade.
One of the things that confuses me is the Pins=. I want to connect my pressure sensors to pin 20 and 21 respectively. In you example you have them P8, P22,P23, P31. I just don’t understand. When I look at my SFG file I see this as well.
The pins you use depends on the type of transducer you are using and the output it provides. My UMA pressure transducer outputs a voltage. It is powered by the aircraft power buss, not SV. The best choice for me was the "Type C" input.
You should be able to use the Type A for most pressure transducers that output 0 to 5 V. Just copy (2 times) a section from your .SFG file that is for the pins you are using. You will have to change the fields: id=new transducer, name=PRES1 or PRES2, Min_val and Max_val, and calibration Coefficients.