Write to an array at index M1?

Hi, thank you for great apps!
In streamfbyter, I would like to preserve some values in array J.
For example I would like to capture incoming CC messages at ch1.
So I filter all messages but B0.
Then I have M1 and M2 which I try to store like this
ASS JM1 = M2 +P This gives me error.


I want to write a code which should write M2 value to array J under M1 index.


If I use additional filtering each CC, then I could use
ASS J0 = M2 +p 
ASS J1 = M2 +p....
ASS J2 = M2 +p  
this one is working, but you know, it isn't a solution.


I need write in array J under index = M1 value from M2.
Please help!
Thanks!