keithr@vice.ICO.TEK.COM (U.D.M.) (12/03/88)
I am looking at building a 5 1/4 drive for my 1040. The pre-built drives are a little more than I can afford right now. Has anyone modified a IBM-PC drive? Is it easy? Pain in the rear? Where might I get some more info. Any feed-back is greatly appreciated. Keith Rast keithr@icogem1.ICO.TEK.COM
ignac@electro.UUCP (Ignac Kolenko) (12/05/88)
In article <3087@vice.ICO.TEK.COM> keithr@vice.ICO.TEK.COM (U.D.M.) writes: >I am looking at building a 5 1/4 drive for my 1040. The >pre-built drives are a little more than I can afford right now. Has >anyone modified a IBM-PC drive? Is it easy? Pain in the rear? about year ago, i added a standard panasonic ibm drive to my 1040. i didn't have too many problems, i just had to make sure to buffer a few of the lines (drive select, motor on i believe, i can't remember off hand), and find a cable with the non standard connector on it. most st stores will carry spare drive cables, which you can canniblize to hook up the ibm drive. finally, get a power supply, and you're all set. the whole shebang cost me about $180 CDN. -- Ignac A. Kolenko "Squeeze my lemon, let the juice run watmath!watcgl!electro!ignac down my leg!" - Led Zep (Lemon Song) "The main energizer's bypassed like a Christmas tree, so don't give me too many bumps!" - Scotty (ST:TWOK)
patrickm@htsa (Patrick Mans E47) (12/06/88)
In article <3087@vice.ICO.TEK.COM>, keithr@vice.ICO.TEK.COM (U.D.M.) writes: > I am looking at building a 5 1/4 drive for my 1040. The > pre-built drives are a little more than I can afford right now. Has > anyone modified a IBM-PC drive? Is it easy? Pain in the rear? > Where might I get some more info. Any feed-back is greatly appreciated. > > Keith Rast > keithr@icogem1.ICO.TEK.COM I have been working on a 5 1/4 drive for my 1040 for quite a while now, but without succes, unfortunately. I was told that the connections from the 1040 are suitable for a standard Shugart(IBM) drive. I only would have to buffer all the lines and get the drive selection right, and then it would work. However it doesn't. I've tried all possible settings, but the only thing that happens is that the motor starts running,... no head movements, and no data output. Could someone fill us both out on this, I'm getting quite desperate. I seem to have lost all faith in my technical abbillity. greetings pat.
to_stdnet@stag.UUCP (12/09/88)
From: dynasoft!john@stag.UUCP (John Stanley) [patrickm@htsa (Patrick Mans E47) writes...] > I have been working on a 5 1/4 drive for my 1040 for quite a while > now, but without succes, unfortunately. > I was told that the connections from the 1040 are suitable for a > standard Shugart(IBM) drive. They are... almost... > I only would have to buffer all the lines and get the drive selection > right, and then it would work. However it doesn't. Getting the drive selection right is more involved than you may think. > I've tried all possible settings, but the only thing that happens is that > the motor starts running,... no head movements, and no data output. > Could someone fill us both out on this, I'm getting quite desperate. I > seem to have lost all faith in my technical abbillity. Don't give up yet... Atari took one shortcut in designing the drive contoller circuits that makes this 100 times more difficult to figure out than it should ever have to be. > greetings > pat. I ran into -exactly- the same problems when I tried to get a 5.25" drive to work on my machine. It's not necessary to buffer -all- the lines. As a matter of fact, the cable I use doesn't have any buffers at all. Just a direct connection between my ST and the drive. (I did, however, have to make a small alteration to my drive....) The drive select circuit on the ST doesn't source enough current to take care of many 5.25" (and a few 3.5") drives. The fix involves first making sure you've removed the termination resistor pack from the 5.25" drive (the internal drive has one already). Next, trace the drive select lines on the disk drive itself to find the drive select pullup (yes, UP) resistor. You'll probably find a 300-400k resistor. If you replace it with a 600 to 1000k resistor, your drive select problems should go away. Good luck... --- John Stanley (dynasoft!john@stag.UUCP) Software Consultant / Dynasoft Systems