From: John Iannetta <76703.4244@CompuServe.COM> Subject: Re: Disk drive step motor Newsgroups: comp.sys.cbm Organization: CompuServe, Inc. (1-800-689-0736) References: <34f329b9.1112505@news.thezone.net> Message-ID: Date: 26 Feb 1998 15:50:07 +0200 Christopher, You said, "I have a step motor out of a commodore64 1541 disk drive and I need to know what wire do I hookup where for a manual test. The step motor is a M68SP-1, 12vdc 33ohms 1.8degree step. It is made by Mitsumi I think, well thats what is says on the back.". You should have two red leads, and one each of yellow, black, orange, and brown. Tie the two reds together and connect them to the positive terminal of a 12 VDC source (capable of supplying 0.5 amperes); connect the negative terminal to ground. Call yellow A, black B, orange C, and brown D. To rotate the motor in one direction, ground (in turn), A, B, C, D (one at a time). For the other direction, the sequence is A, D, C, B. If you have access to a genuine C-64 (NOT an emulator), a small BASIC program and eight transistors, four resistors, and four diodes, can be used to step the motor. Each of four drivers: o to A, B, C, D ! ! ! -----------o-->I----o +12 VDC ! ! C ! 1N4148 ! --B 2N3904 ! ! ! ! E ! !!! ! C 4.7 !!! ! kohm !!! ---------B 2N2219A !!! !!! E ! ! ! ! o GND IN Connect the input of the A driver to pin C of the user port, the B input to pin D, the C input to pin E, amd the D input to pin F. Connect ground to pin A of the user port. Then run this program. 10 p=56577:pokep+2,255:a=1:pokep,a 15 k=2:poke650,128 20 geta$:ifa$="+"thens=s-1 25 ifa$="-"thens=s+1 30 ifa$="c"thenk=1/k:a=8/a 35 ifa$=chr$(13)thenoke650,0:end 40 ifs<0thens=. 45 ifs>99thens=99 50 pokep,a:a=k*a:pokep,a:a=k*a 55 pokep,a:a=k*a:pokep,a:a=k*a 60 ifa=16thena=1 65 ifa=.5thena=8 70 fori=.tos:next:goto20 Pressing "+" increases speed, pressing "-" decreases speed, and pressing "c" changes direction of rotation. -- And the Lord said, "Go forth, and multiply.". And the snake said, "I can't; I'm an adder.". John