|Re: What does your 9114 sound like after a NEWM 050? - does any drive work ?|
Message #8 Posted by Reinhard Hawel on 9 Jan 2000, 10:13 p.m.,
in response to message #7 by Steve
What I wanted to say, is thay you possibly could even use a 1.44 drive, like it's sold for abt $10 everywhere.
The bus (lug and signals) is the same and even the number of tracks (80 = 135 TPI) doesn't differ. The only difference is the number of sectors (DD=9, HD=18 in the IBM PC), which does depend on nothing but the software in the controller, that takes care of the drive (does the physical interfacing with electrical signals).
I dug out a very old Hardware book and they explain, that HD drives commonly had (have ?) jumpers, that differentiate between HD and DD.
The drive must surely "know" the difference, because in an IBM PC there is a line (line 2 on the plug, which tells you, if there's a HD or DD disk in the drive. The guys who are longer in the hardware business know, that one of the holes (the one without the switch) is for differentiating between HD and DD disks.
The drive controller applies the correct signals. In case of an 9114 the controller would always ignore the HD/DD line and format every disk to something abt >600 k (the equivalent of the PCs 720 k).
Please note, that I didn't try this out, but the theory seems to be ok. Somebody, who's in in real despair could try this out as a last resort.
A note about the using HD disks on the 9114: I wouldn't recommend using HD disks on a 9114, just because the heads of this old 720k only drive are not made for the magnetic flux needed to write to a HD disk. Newer (=HD) drives are prepared to use both media, even if the 720 k disk is long deas. I dug in my old PC disks and found lot of 720 k disks. I burnt the data on CD (which I'd recommend anyway, because a disk is a rather risky method of saving valuable data) and set aside the 720 k disks for use with the 9114. Sure, the 1.44 disks will work, but I doubt they'd have the same reliability as the 720k disks.