PD multiplexer capelet example

ManosDim

Hey, I'm using the multiplexer example, but I'm getting wrong readings. I have connected 8 pots to the 1st channel (0.0, 0.1 , 0.2 etc) but I'm getting the values as a column in the terminal. Has anyone experienced the same thing? I want 32 channels and i have flashed my board with the dev branch. cheers!

giuliomoro

that's expected. I think they are printed in a different order in Pd (i.e.: rows and columns swapped), but it should be still pretty straightforward to access the values, just swapping the indexing, isn't it?

ManosDim

Yeah, but how could you access each specific reading from a column? Now I'm receiving the four first readings in the first column: 0 . Is it possible to have only the value from the 2nd row of the column?
1
2
3

giuliomoro

the values read by the muxer are stored as elements in the bela_multiplexer array/table, so you can use tabread or array get to read them off, you just need to produce the right indeces. The number of elements in the array is 8*bela_multiplexerChannels, where bela_multiplexerChannels is 4 when you have 32 analog ins or 8 when you have 64 analog ins. The example patch generates numbers from 0 to bela_multiplexerChannels * 8 - 1 and it prints for each row n the values corresponding to the following indeces:

n * 8 + 0, n * 8 + 1, n * 8 + 2, n * 8 + 3, n * 8 + 4, n * 8 + 5, n * 8 + 6, n * 8 + 7

To get only the second element from the column you need to pass to [tabread] only values of the form n * 8 + 1. If you have 32 channels, that means: 1, 9, 17, 25. E.g.:

alt text

ManosDim

Thanks so much, It is working. The next question is if I could use the multiplexer as digital/analog outputs and inputs at the same time. Will I write to a table with [tablewrite] and the index/output the value (0 to1) that I want?

giuliomoro

ManosDim f I could use the multiplexer as digital/analog outputs and inputs at the same time.

no, the multiplexer only allows to increase the count of analog inputs. The digital I/O and analog outputs are unaffected.

vfillion

Hi @giuliomoro ! Are the values stored automatically in the array in PD ? I am getting the regular C++ example to work with my Multiplexer, but have not yet succeeded on PD. When I run the example, I'm not getting any readings, everything's at zero. Do you somewhere have a tutorial on using the multiplexer with PD ? Thank you so much.