Electrical stimulator for biological tissue having mode control

Claim 1

An electrical stimulator for biological tissue, comprising: storage means for storing a plurality of sets of stimulus parameters; parameter variation means operatively coupled to said storage means for varying the value of at least one of said plurality of sets of stimulus parameters according to a predetermined algorithm; converting means for converting a selected one of said plurality of sets of stimulus parameters to an electrical stimulus output signal which is adapted to be supplied to biological tissue; an operator controlled switch settable to at least two positions; coupling means operatively coupled to said storage means, to said parameter variation means, to said converting means and to said configuration means, said coupling means for coupling a selected one defined by said operable controlled switch upon power-up of said plurality of sets of stimulus parameters to said converting means from said storage means or from said parameter variation means wherein said coupling means selecting a first or a second one of said plurality of sets of stimulus parameters and coupling said parameter variation means to said converting means when said switch is in a first position or a second position, respectively, which is the same position said switch as in during power-up of said electrical stimulator and wherein said coupling means is selecting said second or said first one of said plurality of sets of stimulus parameters and coupling said storage means to said converting means when said switch is in said first position or said second position, respectively, which is a different position from the position said switch was in during power-up of said electrical stimulator.