The Olimex Boards Output

Hello everyone, I’m new and I don’t know where to put this exactly so here it comes!

I’m planning to buy the analog and digital Olimex board

sets, and am planning to make a C++ program to read from the serial port,

however I have the following questions:

1- What is the output of the Olimex digital board exactly, what will I

receive from the serial port?

2- How often does the Olimex digital board send to the serial port, and

hence how often should I read from the serial port?

3- Any suggested methods of comparing the output of the digital board.