Control means for cancelling the first state in response to an instruction other than the second erasing instruction is arranged to be the steps #V-15-1 and #V-15-2 of the subroutine (V) which are provided for allowing the flow of operation to come out of the subroutine (V) after the step #V-18 is executed when the erasion standby switch 77 or some switch other than the switches 77 and 78 is turne