When the scope and definition of the product have become clear, we start by defining the system architecture. The functions of the product will be decomposed in main parts. Decisions will be made with respect to make or buy, implementation in either hardware or software, selection between microcontroller or FPGA etcetera.
For the critical functions of the product main components will be selected, the required interfaces will be chosen and the architecture for the software will be determined. Here selections will be made to use an RTOS, Linux or a bare metal implementation.
Furthermore the required form factor of the product will be discussed, from which is derived whether a physical breakdown of the product in modules is needed.
The results of the system architecture is written down in an Architectural Design Document (ADD).
