Computer system employing docking bay with spring loaded connector pins and file coherency method

A system, comprising:

• a first computer system, including, in one or more physical housings, at least one central processing unit (CPU), program memory, at least one input device, and a display;
• a second computer system, including, in a single hand-portable housing, at least one central processing unit (CPU), program memory, at least one input device, and a display, said housing of second computer system being smaller in overall size than housings of said first computer system;
• a docking bay, comprising a recess which is large enough to accept insertion of said housing of said second computer system, and which is complementary to the external shape of said housing of said second computer system, and which is shaped to constrain said housing of said second computer system to a single direction of motion during insertion;
• wherein said first and second computer systems are each separately operable as fully programmable stand-alone computer systems;
• and wherein said docking bay includes spring-loaded, pogo-type pins mounted in the interior thereof, said pins being positioned to be axially compressed in said single direction when said housing of said second computer system is inserted within said docking bay;
• and wherein said pins of said docking bay are connected to provide a data interface to said first computer system;
• and wherein said second computer system includes contact pads, in the exterior thereof, which are connected to provide a serial data interface to said CPU of said second computer system;
• and wherein said first and second computer systems are configured to automatically detect a connection between said pins and said contact pads, and to automatically call a data transfer program in response to a detection of said connection for transferring files bidirectionally between said first and second computer systems to thereby maintain file coherency.