> just use this routine to turn off yer calc(it will turn back on when you > press [ON]) > ld a, 1b > out (3), a > di > halt > ei > ld a, 1011b > out (3), a Hmm... But that won't get the calc into low-power mode, now does it? I'm not sure though, what it dows, but the name kinda hints, that the batteries will last longer.... ;) (and then I could leave the calc off my own way for a longer time...)