Power up/power down for electronic hardware which conserves electric power

A system for changing a state of electronic equipment which is operated from a power source from a power down state to a power up state by operation of any key of a keyboard which provides data entry signals via a plurality of data lines, said system comprising:

• a power flip-flop which has a power on output and a power off output and inputs which change the flip-flop between set and reset states,
• a first isolation switch connected to said flip-flop for conditioning said flip-flop into the one of the set and reset states which provides the power on output when any key of said keyboard is actuated, and
• a second isolation switch through which said data entry signals are transmitted, and one of said outputs from said flip-flop being connected to said second isolation switch for opening said second isolation switch to prevent said data entry signals from being transmitted except when said flip-flop is in said one of the set and reset states,
• wherein said system is continuously operated by direct connection to said power source,
• wherein said equipment is operated from said power source via a power supply which interconnects said power source and said equipment,
• wherein said power supply is switchable between an on state and an off state, and said power supply is in said on state when said power on output is asserted, and said power supply is in said off state when said power off output is asserted, and
• wherein said system further includes a serial data line input to said flip-flop for conditioning said flip-flop into the one of the set and reset states which provides said power on output when serial data is provided on said serial data line.

A system for changing a state of electronic equipment which is operated from a power source from a power down state to a power up state by operation of any key of a keyboard which provides data entry signals via a plurality of data lines, said system comprising:

• a power flip-flop which has a power on output and a power off output and inputs which change the flip-flop between set and reset states,
• a first isolation switch connected to said flip-flop for conditioning said flip-flop into the one of the set and reset states which provides the power on output when any key of said keyboard is actuated, and
• a second isolation switch through which said data entry signals are transmitted, and one of said outputs from said flip-flop being connected to said second isolation switch for opening said second isolation switch to prevent said data entry signals from being transmitted except when said flip-flop is in said one of the set and reset states,
• wherein said data entry signals comprise strobe signals, said strobe signals being periodically present on at least one of said plurality of data lines, and said first isolation switch connecting said keyboard data lines to said flip-flop for conditioning said flip-flop into the one of the set and reset states which provides said power on output when any key on said keyboard is actuated.

A system for changing a state of electronic equipment, which is operated from a power source, from a power down state to a power up state by operation of any key of a keyboard which provides data entry signals to data utilization equipment via a plurality of data lines, said system comprising:

• a microprocessor having inputs for sensing signals,
• a power flip-flop which has a power on output and a power off output and inputs which change the flip-flop between set and reset states,
• a keypad in which a plurality of keys are disposed in an R.times.C matrix, where R and C are non-zero integers, said keypad consisting of R rows and C columns, said R rows being each connected to a corresponding one of R lines of a row data bus, and said C columns being each connected to a corresponding one of C lines of a column data bus, and said row data bus connects each of said R rows to a corresponding one of R outputs of a strobe signal generating means, and said column data bus connects each of said C columns to a corresponding one of C inputs of said data utilization equipment and said strobe signal generating means successively generates a signal one each of said R lines, and said inputs of said microprocessor continually sense signal levels of each of said C lines, so that depressing a key located in the Ith row and the Jth column causes said inputs of said microprocessor to sense a data entry signal at the Jth line when the Ith line is strobed, thereby decoding keypress information,
• said system further comprising:
• a first isolation switch connected to said flip-flop and connecting said row data bus lines to said flip-flop for conditioning said flip-flop into the one of the set and reset states which provides said power on output when any key of said keyboard is actuated, and
• a second isolation switch, connecting said column data bus and said inputs of said microprocessor, and through which said data entry signals are transmitted, and one of said outputs from said flip-flop being connected to said second isolation switch for opening said second isolation switch to prevent said data entry signals from being transmitted except when said flip-flop is in said one of the set and reset states.