Hello All!Yesterday i was make a FS Stepper board. It Flashed ok and CID assigned to AT90S2313-10PI.When i was test the board.. i was assign a FS Sourse (Flaps indicator) and start experiment. Supply voltage is 12V. Then flaps is moving i see a 5V at 1,2,3,4 pins to ground. That is OK? Regards, Alexander.

A stepper motor is driven by powering each set of coils in order, in differnt directions. So for a 12v motor, let's assume pins 1 & 2 are for one coil and 3 & 4 are for the other, this table shows a typical rotation pattern...Pin......1......2......3......4........+12v...gnd.....0......0.........0......0.....+12v...Gnd........Gnd...+12v.....0......0.........0......0.....Gnd....+12v(stupid board takes out spaces or tabs so I had to put in dots to keep the columns :-()The fluctuating value across the pins would therefore show up on an analogue voltmeter as a value less than 12v.... 5v is not unreasonable.Richard

Thanks for answer..I connect stepper yesterday.. i use uni-polar type of motor (taken from old copier. minebea pm35-48).. it works fine, but makes really hot :( ( 60-70 degree)..is this ok?

In Mike Powell's book "Building Simulated Aircraft Instruments", he uses plastic gears to make the steps smaller. For instance, a 2:1 gear ratio will give you 30 degrees of movement vs. the 60 degrees. You can easily adjust your faceplate settings to reflect the flap movement you want to show.So your motor can work.John