Yes, i read your post and based my idea in your post.

I also completemented it by adding the 4x4 keypad to make the strings of 5 bytes because he need to input this "40 bits"

I understood that he wants to recieve 40 strings of 5 bytes and then process the data that is where the keypad comes

I think i clarified his problem. if not he can have an idea of what i think he is trying to said, and he can help me to help himself by telling more about this project