ralph@laas.fr (Ralph P. Sobek) (08/24/90)
Some time back there were numerous postings concerning the (in?)famous Chinon floppy drive. As I remember, many people had problems with its media change detection. What were the conlusions of those postings? My new Mega 4 ST has a Chinon Rev B F-354 EAA drive in it. It has been sent back to the dealer to fix the `media change problem'. I'm curious as to what official solutions that were made available. Suggestions are also appreciated. Is there a good test program for this problem? Please try to reply to me directly and I'll summarize if anyone else is in the same boat, and interested. -- Ralph P. Sobek Disclaimer: The above ruminations are my own. ralph@laas.fr Addresses are ordered by importance. ralph@laas.uucp, or ...!uunet!laas!ralph If all else fails, try: sobek@eclair.Berkeley.EDU =============================================================================== Reliable software should kill people reliably! -Andy Mickel, Pascal News #13,78
jhenders@van-bc.wimsey.bc.ca (John Henders) (08/27/90)
Here in Canada,there appears to have been NO official recognition of the problem. My complaints were tested by my local tech after installing TOS 1.4 from the desktop only,so the problem wasn't found. Unfortunately other programs using their own file selectors don't benefit from TOS 1.4s fmc hack. A friendly dealers solution was to swap in a drive from a machine going back to Atari for other problems (I'll never tell who). Perhaps Bob Brodie,who has showed up here a few times from an account on portal could clarify what's going onm. John Henders
grahamt@syma.sussex.ac.uk (Graham Thomas) (08/29/90)
From article <RALPH.90Aug24125733@orion.laas.fr>, by ralph@laas.fr (Ralph P. Sobek): > Some time back there were numerous postings concerning the (in?)famous > Chinon floppy drive. As I remember, many people had problems with its > media change detection. > > What were the conlusions of those postings? My new Mega 4 ST has a > Chinon Rev B F-354 EAA drive in it. It has been sent back to the > dealer to fix the `media change problem'. I'm curious as to what > official solutions that were made available. > > Suggestions are also appreciated. Is there a good test program for > this problem? I'm not sure about the current state of Chinon drives on the Mega, but the external floppy drive I bought recently had the 'media change' problem. It was sold by a large UK distributor, Evesham Micros, and I don't know how widespread it is elsewhere in the world, but it's made by a firm called Roctec and it's called something like RF 302. It's advertised as having a Teac or Citizen mechanism - I guess it depends on the batch. Anyway, it's now back with Evesham with a request for replacement. The easiest way I found to test the existence of the problem is this: 1. Insert disk #1. Open any folder 2. Remove disk #1 and insert disk #2. You'll still see the drive window displaying disk #1's folder. This is normal. 3. Click on the top left corner of the window (the 'close box') to return to the top directory. A fully-working drive will proceed to read the disk, recognising that the media 'might have changed' and will then show the top directory of disk #2. A faulty drive not read the new disk and will show the top directory of disk #1. You can force the ST to read the new disk in a faulty drive by pressing 'escape' (at least, this works on TOS 1.4 and above; I'm not sure if it works for all TOS versions). The fault is easy to spot if you're at the desktop, but might not be so easy if you're writing to a disk when inside an application. There's a considerable danger that you'll mess up the file allocation table on the 'new' disk, as the ST will think it's writing to the free space on the 'old' disk. The only mitigating factor is that if you had to swap disks because there was not enough free space on the old disk, the ST won't overwrite the new disk because it will still think there's not enough free space. Graham. -- Graham Thomas, SPRU, Mantell Building, U of Sussex, Brighton, BN1 9RF, UK JANET: grahamt@uk.ac.sussex.syma BITNET: grahamt%syma.sussex.ac.uk@UKACRL INTERNET: grahamt%syma.sussex.ac.uk@nsfnet-relay.ac.uk UUCP: grahamt%syma.sussex@ukc.uucp PHONE: +44 273 686758 FAX: [..] 685865
exspes@gdr.bath.ac.uk (P E Smee) (08/29/90)
In article <RALPH.90Aug24125733@orion.laas.fr> ralph@laas.fr writes: >Some time back there were numerous postings concerning the (in?)famous >Chinon floppy drive. As I remember, many people had problems with its >media change detection. > >What were the conlusions of those postings? My new Mega 4 ST has a >Chinon Rev B F-354 EAA drive in it. It has been sent back to the >dealer to fix the `media change problem'. I'm curious as to what >official solutions that were made available. I worked up a fix for the problem mechs at the time when Cumana was using them. I wrote to Cumana describing the problem and my fix; I got a letter back saying they'd discussed it with Chinon and my fix was 'suitable and appropriate'. Don't know if the publicised it. IF you are comfortable with taking your ST apart, what you do is: Remove the drive mech. Looking into it, you'll see there are 2 little pin switches, one of which is located where the write-protect hole in the disk is, and a second right next to it. The first is the write-protect sense switch; the second is a 'disk present' switch. The internal circuitry of the Chinon drive means that the WP switch state doesn't get sent to the ST unless the disk present switch is closed. The 'fix' is to make the disk-present switch be permanently closed. The way to do this is to solder a small jumper wire across its terminals on the bottom of the drives PC board. In my drive, both switches were in a single unit, but it was obvious which set of terminals went to which side. NOTE --- I don't know if all Chinon drives with the problem are constructed the same way, so neither I nor anyone else I've mentioned can be held responsible if you try this and it breaks things. All I will commit to is that it worked fine for me... I've fixed 2 Chinon mechs that way. (It's a good way to get a reliable CHEAP mech -- there are a lot of them flying around, presumably because people have discovered they don't work on STs. Unless you perform the trivial modification.) ALSO NOTE -- Not all Chinon drives have the problem. In particular, Cumana claimed that they were going to switch to a different model of Chinon mech which worked properly in this regard. >Suggestions are also appreciated. Is there a good test program for >this problem? Please try to reply to me directly and I'll summarize >if anyone else is in the same boat, and interested. There's a simple test _procedure_. Put a write-enabled floppy (little window closed) in the drive, and pop up a directory-listing window. Take the floppy out, reinsert it (or any other write-enabled floppy) and hit ESCape. If the drive spins, you're OK. If the drive does not spin, you've got the problem. The problem mechs only do the wrong thing with write-enabled disks. To be sure, try this several times . -- Paul Smee, Computing Service, University of Bristol, Bristol BS8 1UD, UK P.Smee@bristol.ac.uk - ..!uunet!ukc!bsmail!p.smee - Tel +44 272 303132
storkamp@sj.ate.slb.com (Mark Storkamp) (08/30/90)
In article <1990Aug29.100251.11916@gdr.bath.ac.uk> P.Smee@bristol.ac.uk (Paul Smee) writes: >In article <RALPH.90Aug24125733@orion.laas.fr> ralph@laas.fr writes: >>Some time back there were numerous postings concerning the (in?)famous >>Chinon floppy drive. As I remember, many people had problems with its >>media change detection. >> >>Suggestions are also appreciated. Is there a good test program for >>this problem? Please try to reply to me directly and I'll summarize >>if anyone else is in the same boat, and interested. > >There's a simple test _procedure_. Put a write-enabled floppy (little >window closed) in the drive, and pop up a directory-listing window. >Take the floppy out, reinsert it (or any other write-enabled floppy) >and hit ESCape. If the drive spins, you're OK. If the drive does not >spin, you've got the problem. The problem mechs only do the wrong >thing with write-enabled disks. To be sure, try this several times . > One of the changes in TOS 1.4 is it now forces a re-read of the disk whenever you hit ESCape, even if a media change was not detected. This, unfortunatly, will not fix the problem if you change disks while inside of a program. It does make it much more difficult to tell if you have this problem. The procedure outlined above will work from Neodesk, since it does not force the re-read. Mark Storkamp