HELP! 15 possible input combinations -> 15 diff. analog values (1AO)

I think this is a question for the experts, I can't figure it out to write a program less complex then this in the attachment.

Short intro, 4x digital inputs (4DI) and 1x analog output (1AO). Each input or combination of inputs needs to send a specific (fixed) value to an anlog output.

Use: status fume hoods (labo) -> control VAV-unit (Variabel Air Volume)

Looks easy but don't forget that the "total" of DI-combinations is 15!

I1 -> analog value 1

I2 -> analog value 2

…etc

I1 & I2 -> analog value 5

I1 & I3 -> analog value 6

…etc

I1 & I2 & I3-> analog value 10

I1 & I2 & I4-> analog value 11

…etc

I1 &I2 &I3 & I4 -> analog value 15

At the moment I use a lot of multiplexers with the combination of mathematics, comparators to calculate the highest analog value.

No,no, way too complex but it works, unfortunately without a detailed explanation no one will understand.

At first I thaught to use 15 flags (DI comb.) and also to use 15 predefined analog values -> that's easy (like in our bigger PLC's, data in DB's)

But I can't see any possibility how to store the15 predefined analog values, I'm missing something?

Is there anyone outhere who can figure this out or does I need to choose the complex way like the example?

Any help will be very appreciated.

Many thanks, Dave

Dear ixo65,

your solution V3 was what I needed.
Many thanks for your cooperation!

Although I don't understand how to use VM, this solution works "super".

Your solution with the 15 options is actually for a "single" room, in total 5 rooms need to be checked in such a way.
Based on your example, I have written a separate program for each individual room and then tested -> works perfectly.

The next step was the combination of the various individual programs into a single combined program.
There it goes wrong, during simulation there is an interaction of the different digital inputs.

 
For example: the first three inputs (I1, I2, I3) send a correct value to AQ1-> that's good.
BUT these 3 inputs also affect the analog output value of AQ2, AQ3, AQ4 regardless of the status of I4, I5, etc ...

However, all the entrances to each individual room were provided with a separate address to the VM, as follows:
Room 1 -> I1, I2, I3               -> V1.0, V1.1, V1.2            & VW 0
Room 2 -> I4, I5, I6, I7          -> V2.0, V2.1, V2.2, V2.3   & VW 1
Room 3 -> I8, I9                    -> V3.0, V3.1                      & VW 2
Room 4 -> I10, I11, I12, I13  -> V4.0, V4.1, V4.2, V4.3   & VW 3
Room 5 -> I14, I15                -> V5.0, V5.1                      & VW 4

Since I do not yet understand how you can extract something from the VM, I assume that the parameterization of the network outputs and the network analogue inputs as above is probably wrong?

Attached the separate programs for each room separately, these work as expected.
Also attached the program with all rooms combined, there the analogue outputs are influenced by the status of the first inputs -> that's wrong :(

To make the program readable, I have placed all the rooms on a separate page.
First page = room 1, second page = room 2, etc …

To easily reformulate the question:
in every room (page) there is an analogue output and this may be "only" influenced by the digital inputs in the same room (on the same page).
Why does the status of the inputs of, for example, room 1 affect the output of room 3?

Many thanks to figure this out.
I do not see the problem and therefore cannot find the solution.

Hi ixo65,

you're great but you probably already knew that!

Thanks to your explanation and specifically the schematic representation of "bit, byte, word" was very helpful and educational.
At least now I understand where my mistake was and I will no longer make it.

5 stars for you, well deserved!

Thank you!!

Thanks a lot for this nice piece of "code" ;-)

Still, I'd like to ask how I could achieve this - I have made many attempts but non worked yet :-(

This program is obviously not working - it's just meant to explain what I'd like to achieve ;-)

Thanks for any help.

No, the math block is only there to link the digital world to the analog one.

I don't even know what blocks I should really use.

I'm confused....

As said, this program is only the expression of my mind, of my goal - it is actually certainly not how it has to be made.