blgardne@esunix.UUCP (Blaine Gardner) (06/29/87)
A question that has occured to me while trying to get an 80 track 5.25"
drive to work on my Amiga: Why don't 3.5" drives have to be "mounted"?
What "magic" is there in the 3.5" drives that allows them to be
automatically recognized by the system, that the 5.25" drives don't
have?
--
Blaine Gardner @ Evans & Sutherland
UUCP Address: {ihnp4,decvax}!decwrl!esunix!blgardne
Alternate: {ihnp4,seismo}!utah-cs!utah-gr!uplherc!esunix!blgardneford@crash.CTS.COM (Michael Ditto) (06/30/87)
In article <384@esunix.UUCP> blgardne@esunix.UUCP (Blaine Gardner) writes: >What "magic" is there in the 3.5" drives that allows them to be >automatically recognized by the system, that the 5.25" drives don't >have? The system asks each drive for its 32-bit type-code, and simply ignores drives that do not reply with the standard 3.25" ID code. Other drives are still available through OpenDevice(), but not automatically mounted by the DOS. -- Michael "Ford" Ditto -=] Ford [=- P.O. Box 1721 ford@crash.CTS.COM Bonita, CA 92002 ford%oz@prep.mit.ai.edu
daveh@cbmvax.UUCP (Dave Haynie) (07/01/87)
in article <384@esunix.UUCP>, blgardne@esunix.UUCP (Blaine Gardner) says: > Keywords: why > > A question that has occured to me while trying to get an 80 track 5.25" > drive to work on my Amiga: Why don't 3.5" drives have to be "mounted"? > > What "magic" is there in the 3.5" drives that allows them to be > automatically recognized by the system, that the 5.25" drives don't > have? Neither drive has to be mounted if it has an Amiga recognition circuit on it, as do both the C-A 3-1/2" drive and the C-A 5-1/4" drive. On startup, the system polls drives DF1: and beyond for a string of 32 bits on the RDY line. An 80 track drive sends the string "FFFFFFFF", a 40 track drive sends the string "55555555", and if no drive is in that slot the "00000000" string is returned. If there's interest (when I've got a few more minutes), I'll post how this can be done with simple hardware. > Blaine Gardner @ Evans & Sutherland -- Dave Haynie Commodore-Amiga Usenet: {ihnp4|caip|rutgers}!cbmvax!daveh "The A2000 Guy" BIX : hazy "Catch a wave and you're sittin' on top of the world" -Beach Boys
sbmueller@watmath.UUCP (07/18/87)
In article <2061@cbmvax.UUCP> daveh@cbmvax.UUCP (Dave Haynie) writes: > >Neither drive has to be mounted if it has an Amiga recognition circuit on >it, as do both the C-A 3-1/2" drive and the C-A 5-1/4" drive. On startup, >the system polls drives DF1: and beyond for a string of 32 bits on the RDY >line. An 80 track drive sends the string "FFFFFFFF", a 40 track drive sends >the string "55555555", and if no drive is in that slot the "00000000" string >is returned. If there's interest (when I've got a few more minutes), I'll >post how this can be done with simple hardware. Please do tell then, why must I still do a mount on my 5.25" official C-A drive, to use it under WB1.2? It is obviously, as you say, recognized by the machine (eg. the Transformer knows about it without a mount) Also, why do I get DF1:BAD, DF2:BAD, DF3:BAD if the 5.25 isn't turned on? What can I do to stop this (besides always turn on the drive). More questions: What must I do to the animal to have it do automatic diskchanges? (I've had it longer than the warranty, so I ain't worried about breaking nuthin.) Finally, is there any news on the new and improved Transformer? Thank you for taking the time to answer/ignore my probably painfully stupid, frequently asked questions. > >-- >Dave Haynie Commodore-Amiga Usenet: {ihnp4|caip|rutgers}!cbmvax!daveh >"The A2000 Guy" BIX : hazy > "Catch a wave and you're sittin' on top of the world" -Beach Boys APD: ||~ (all purpose disclaimer: Or Not) -------------------------------------------------------------------------------- "Na na na naaa" - The Beatles Amiga (TM?) "Who Ha, Whoha" - FGTH This space // Bizarre/Design "Aah, aah" - Queen currently // Twisted/Fate under \\ // DY/DX "Has anyone seen my marbles?" construction. \// Body/Fisher - SBMUELLER@WATMATH.UUCP Freak --------------------------------------------@-#$--!@#$--$----#$%^&* parity error
daveh@cbmvax.UUCP (Dave Haynie) (07/21/87)
in article <13964@watmath.UUCP>, sbmueller@watmath.UUCP (Stephan Mueller) says: > > Please do tell then, why must I still do a mount on my 5.25" official C-A > drive, to use it under WB1.2? It is obviously, as you say, recognized > by the machine (eg. the Transformer knows about it without a mount). Sounds like maybe a 1.2 feature? Having no need for the beast myself, I've never used a 5.25" drive, but I do know the hardware well enough to state that the system is capable of adding it in without a mount if the software designers had decided that was a good thing to do. Perhaps it's left as an option so that thing like the PC Disk utilities work OK. > Also, why do I get DF1:BAD, DF2:BAD, DF3:BAD if the 5.25 isn't turned on? All your disks are daisy-chained together, sharing common data and control lines. If you don't supply power to the 5.25" drive, but leave it connected, those common lines will be affected by the undefined action of the switched off IC inputs. This undefined action is usually not a good thing, I've seen it cause problems in machines long before the Amiga came out. > What can I do to stop this (besides always turn on the drive). Disconnect it. > What must I do to the animal to have it do automatic diskchanges? (I've had > it longer than the warranty, so I ain't worried about breaking nuthin.) The diskchange signal is usually a function of the drive mechanism. There's a microswitch of some kind in the 3.5" drive's pushbutton that results in the open-collector level /CHNG signal from the drive to be asserted (pulled low, in this case). With a little bit of re-engineering of your disk eject button to trigger a microswitch, and maybe an extra TTL chip or two, you could probably add this to the 5.25" disk. The best thing to do would be to 'scope out exactly what the 3.5" /CHNG signal looks like, and then build a similar thing on the larger drive. -- Dave Haynie Commodore-Amiga Usenet: {ihnp4|caip|rutgers}!cbmvax!daveh "The A2000 Guy" PLINK : D-DAVE H BIX : hazy "Catch a wave and you're sittin' on top of the world" -Beach Boys