AMLXX@campus.swarthmore.EDU (09/21/88)
I have had a problem with my internal floppy drive in my 1040 ST. The
top head is coming off! I noticed that there was problem when I was
getting some strange data read every once in a while. Anyway, the
small plate that the head is attached to is supposed to be glued on to
the plastic part of the head positioning mechanism. Unfortunately, the
glue isn't holding so well. Right now the top head is close to dangling.
QUESTION :
Is it OK to glue the plate back on? Since one edge of
Is it OK to glue the plate back on? Since one edge of
the plate is still on, I could place it fairly accurately at the original
place. How accurate does it have to be?
QUESTION 2 :
Is it possible to hook up an IBM XT or AT compatible
drive internally or externally to an ST? What's the difference
between and internal drive and an external drive besides the casing
and the price? What differences are there in cable connectors?
I know that the external Floppy Port on the ST takes a round cable and
the internal drive connects to the board via a long flat connector
with many more pins than an external drive connector. What are all the
extra pins for? Are they all used?
MAYBE! : Could a 1.44 meg drive be hooked up via the internal
drive connector?
note : I have had my computer for slightly over 2 years. It would make
Does anybody know how long other 3.5" drives hold up before they have
problems?
Any advice would be appreciated greatly!!
Sincerely,
Alan M. Levi
===================================================================AMLXX@campus.swarthmore.EDU (09/22/88)
I solved my hanging head problem. A strip of masking tape is now holding my disk drive head in place. It runs fine!! -Alan Levi
42_145@uwovax.uwo.ca (RIC WHEELER) (09/24/88)
WHEN I CONVERTED FROM SINGLE TO DOUBLE-SIDED DRIVES ON MY 520STFM I USED REGULAR IBM-TYPE DRIVES. I HAVE TWO 3 1/2" AND ONE 5 1/4"(FOR PC DITTO).I DECIDED TO MOUNT ALL THE DRIVES EXTERNALLY.THE THREE DRIVES ARE POWERED BY AN OLD IBM POWER SUPPLY WHICH I OBTAINED WHEN A FRIEND UPGRADED HIS PC TO A HEAVIER POWER SUPPLY. AS FAR AS HOOKING UP THE DRIVES,DRIVE ZERO WAS EASY.JUST EXTEND THE RIBBON CABLE FROM INSIDE AND PLUG IT DIRECTLY ONTO THE NEW DRIVE.THE PINOUT IS THE SAME.YOU WILL PROBOBLY HAVE TO REMOVE THE TERMINATING RESISTOR PACK FROM THE DRIVE AND I ALSO FOUND THAT I HAD TO REMOVE THE TERMINATING RESISTOR FOR THE DRIVE SELECT LINE WHICH WAS A SINGLE OHM RESISTOR.THIS MAY BE DIFFICULT TO FIND BUT IF YOU HAVE A TECHNICIATYPE FRIEND HE MAY BE ABLE TO HELP.IT'S QUITE EASY WITH AN OHMETER ON THE DRIVE SELECT PIN. FOR DRIVE 1 I MADE A CONVERSION CABLE FROM THAT FUNNY ROUND CONNECTOR TO A 34 PIN EDGE CONNECTOR.THE PINOUTS ARE AS FOLLOWS ATARI--------1--READ DATA--------------30------EDGE CONNECTOR 2--SIDE 0 SELECT-------32 3--LOGIC GROUND-----------ANY ODD NUMBER 4--INDEX PULSE------------8 5--DRIVE 0 SELECT---------10 6DRIVE 1 SELECT---------12 7--LOGIC GROUND-----------ANY ODD NUMBER 8--MOTOR ON---------------16 9--DIRECTION IN-----------18 10-STEP-------------------20 11-WRITE DATA-------------22 12-WRITE GATE-------------24 13-TRACK 0----------------26 14-WRITE PROTECT----------28 I HOPE THIS IS OF SOME HELP TO YOU. AS FAR AS GLUEING THE HEAD BACK ON YOUR ORIGINAL DRIVE,I PERSONALLY,WOULD JUNK IT.THE SLIGHTEST BIT OF GLUE BETWEEN THE HEAD AND THE GIMBAL WOULD MAKE THE HEAD RIDE AT AN ANGLE TO THE DISK,CAUSING TROUBLE.BUT THEN AGAIN MAYBE LESS TROUBLE THAN A LOOSE HEAD.YOU WOULD CERTAINLY NEED TO CHECK THE ALIGNMENT AFTER THIS DELICATE OPERATION. GOOD LUCK.
MARCUS@STOAT.PCL.AC.UK (10/26/88)
Hello, I wonder if anyone could help me with a query from an ST owning son of one of my work colleagues? He's just picked up a Technomatic double 3.5" double sided disk drive (that's two double sided drives in one box!) for a paltry sum and wants to know if he can get it working on his 520ST. It's rigged up for a BBC Microcomputer (one of those strange things UK educational establishments favour) so it needs conversion but I imagine it"s probably pretty standard IBM type. I figure there must have been articles published on such conversions (I know there has been such an article for the Amiga) - anyone got any ideas? Thanks in advance, - m a r c u s - (ex info-atari8 subscriber, now i-amiga subscriber - no flames pleeeeeease!) -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= marcus@uk.ac.pcl.stoat - JANET "The streets are crammed with marcus%stoat.pcl.ac.uk@ukacrl - BITNET/EARN things, eager to be held..." -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
emmo@moncam.co.uk (Dave Emmerson) (07/30/89)
Since this may be of general interest, I'll post it here, rather than reply directly. All the disk drives I have ever seen, hard or floppy, have a jumper on their pcb near the data connector, which allows you to set its device number. Some only allow you to set it to 0/1 (a/b), most have 4 possible settings. No rewiring is needed, just find the appropriate link and move it to its new setting. If you are at all unsure about this, sketch all the link positions before you move any, and use a disk you won't mind reformatting to test it with. The links are often marked DX and usually numbered either 0 to 3 or 1 to 4. DONT touch any marked MO, TB1, TB2, DCG, MN, PAR. Problems.. The following is a brief note of 2 of the causes of my own disk drive problems over the years. Both can cause intermittent or seemingly permanent problems on any computer. a) using the wrong type of floppy disk. Seems too obvious? I bought a box of re-marked Sony DSDD floppies from a local (normally reputable) supplier. They worked fine for weeks, then I started 'losing' files. It was some months before I found out that they were only single density. All that work salvaging files.... Aaaagh! (I didn't suspect them as I could see the removed Sony legend under the new print. It was only when I looked much more closely that I saw they were SD.) Using HD disks on a DD only drive isn't a good idea either. b) Power supply overloaded/out of adjustment. This one can be much more sneaky. The +- 5% tolerance quoted in many drive manufacturers' specs is often optimistic. I have had drives fail with their 12 volt rail over the 11.5v this allows. Due to bitter experience I *never* use a drive with its 12v supply under 12v, I'd rather have it nearer its upper limit. Linear power supplies often exhibit a tendency to droop a little in the wee hours when mains supply voltages frequently drop by 10% from their norm in my area at least. (The supply company are probably breaching a statutory regulation). To check this, you'll need a 20v meter or an accurately calibrated 'scope. The ground (0v) pins are the middle two on the drive, with +5v one side, +12v the other. If they read OK when you first check, keep everything handy till things start going wrong. Curing this problem is a little more tricky. Many switch mode supplies have no adjustment, some others have only one adjustment, - for the +5v rail. The other outputs are designed to be 'in spec' when the 5v is correctly set up and supplying its correct load. If you are overloading it slightly it won't trip the protection circuit, but the other output(s) is (are) 'starved' for current so their voltages drop. It should read between 5.0 and 5.4v. at the drive. Normally the 12v rail will drop long before the 5v does. Supply voltages DO drift a little as components age, and a 6 monthly check/readjustment by a competent engineer is common practice in industry. BEWARE though, some types of supply can hold a potentially LETHAL charge even when switched off. By all means check it yourself, but unless you know what you are doing, get a qualified technician to service it for you! Do make sure that the power supply gets plenty of fresh air. Burying it under piles of printout etc. is asking for trouble. So is letting it fill up with dust and fluff. For that matter, your ST needs some ventilation too, don't use it on a carpeted floor or on top of your bed or you'll block the vent slots. If all this helps anyone at all it'll be worth its bandwidth. Dave E.