Arduino N channel read

Hi everyone,
below is the part of my project handling I/O pins of my Arduino mega. I encounter a problem when trying put the "output values" of digital read.vi into a cluster. No matter how many pins i read into the DI channel, it always ends up being 9 elements in the output. In this example I am trying to read 21 pins ("Keyboard" consists of 21 elements) into the digital read (the two read VI's combined).

Does anyone know what I am missing?