Abstract: A computer system having a suspend/resume capability in addition to the normal operating state and the off state. Closure events of single momentary pushbutton switch control changes between the normal operating state, the suspend state, and the off state, depending on the value of a flag. If the flag is set in a certain state, closure events of the switch cause the computer system to change back and forth between the normal operating state and the off state. If the flag is set in a different state, closure events of the switch cause the computer system to change back and forth between the normal operating state and the suspend state. The switch also controls the video subsystem of the computer system such that pressing the switch blanks the video display terminal giving the user instantaneous feedback of the switch press.

Abstract: A computer system with an internal operating system located in ROM is initialized in that operating system but can also automatically be directly initialized in an operating system of choice such as one located on an external memory, that is, a diskette or fixed disk. The computer system may also automatically be directly initialized in an application running under the internal operating system and, if desired, initialization may automatically directly include a customized version of the internal operating system. These customizing features are obtained through a customization word located in permanent read/write memory.