All computers have to have some form of input or output in their execution. This will be one of the following:
Neither input nor output — A box that does not do anything!
Input only — Those status reports for your manager that never get read.
Output only — Always talking but never thinking!
Input and output — A (hopefully) useful computer
This chapter discusses one method needed to allow for the input and output of data. There is usually a BIOS or software library that you can use that encapsulates the hardware known as the BSP (board support package), but if you are programming an application that requires direct port access, read on! For example, the communications API in Win32 does not give you time stamps or error status on each ...