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-
- Some Text about adding INTERNAL df2: and df3: to a A1200 Tower
- or whatever.....
-
- ;--------
-
- Legal and whatsoever things:
-
- THIS INFORMATION IS FOR EXPERIENCED HARDWARE HACKERS ONLY. IF YOU DON'T KNOW
- WHAT YOU'RE DOING, STOP IMMEDIATELY. I'D HATE TO SEE/HEAR YOU DESTROYING YOUR
- AMIGA BY FAILING TO CONNECT THIS HACK TO IT. I WON'T ACCEPT ANY
- RESPONSIBILITY OF HARD/SOFTWARE DAMAGE CAUSED BY THIS INFORMATION. IT'S YOUR
- OWN RISK. I CAN'T GUARANTEE ALL DETAILS IN THIS INFORMATION TO BE CORRECT OR
- VALID IN ANOTHER AMIGA.
-
- WHAT COMES TO ME, THIS INFORMATION MAY BE DISTRIBUTED FREELY AS LONG AS
- NOTHING HAS BEEN CHANGED IN IT. ARCHIVING PERMITTED.
-
- ;----------
-
- Hi, I'm Troy McLure. You may remember me from 'How to replace a wall socket
- without turning off the electricity' or 'How to get bumped by a car and
- survive it'.
-
- ..eh... wrong topic. Sorry.
-
- I've built an A1200R, rack-mount cased computer. It has a 200W PoWaSuPpLy,
- two 3.5in hard disk sites (of which one populated), two 5.25in floppy
- sites (of which one populated by CD-ROM drive), two 3.5in floppy sites (of
- which ONLY ONE populated). Still, I can't connect more than one internal
- floppy drive. Of course I could use external drive, but that's kinda... rude.
- After all, I've got a case with enough floppy drive holes in its front panel!
-
- That's gonna stop right now! I built a piece of hardware to get more drives.
-
- The piece of hardware creates autoconfiguration signals to make Amiga recognise
- the drives after reset and memorize if each drive's motor is on or off.
- And, of course, get all drives supplied with PoWa and other signals, that
- are common to all drives.
-
- I'm not gonna bore you with any timing charts
-
- 1 ----- --- --- ----
- | | | | | |
- 0 --- --- ---
-
- or that $FFFFFFFF means no drive and $55555555 means a 3.5in drive and so on.
- TTL ICs have never become familiar to me. I just looked, what pin to connect
- to what pin and so on.... Raw 'schema' is in 'df2+3.pic', I got nothing better
- than that to build my hardware, except that I got an A500 schematics to look
- for details and make sure that connections at least made sense.
- I built it on a piece of 'vero' board (that... printed circuit board, that
- has a LOT of holes in it and just a teenie-weenie pieces of copper around
- them) and it worked fine when I tested it.
-
- Because this construction has many ways to fit it in your system, I'll just
- explain the principle. You may want to connect only one extra drive, so you'll
- build logic for only... say df3:.
-
- Usage of 7474 (dual D flip-flop) is quite funny in this hack. Only half of
- it is in use and there's two of them...
-
- We'll lead all floppy signals from motherboard to df0: as usually.
- Then we'll create _MOTOR2 and _MOTOR3 signals as well as _SEL2' and _SEL3'
- and inject them to the same cable that connects df0:. That requires a special
- (I mean a SPECIAL!) cable to be made. Otherways, however, we'd have to make
- a PCB that contains three 34-pin connectors, one for incoming signals,
- one for df2: and one for df3:. That would make usage of vero board rather
- impossible. Since I don't have equipment for making two-sided PCBs, I
- chose this way. All common signals continue from df0: to df2: and df3: and
- we'll just add those _selects and _motors.
- In our PCB's 34-pin connector we'll connect _SEL2' to pin 10, _MOTOR2
- to pin 16, _SEL3' to pin 12 and _MOTOR3 to pin 14. After df2:'s connector
- we'll cut off _SEL2' and _MOTOR2 and re-route wire 12 (_SEL3') to pin 10 and
- wire 14 (_MOTOR3) to pin 16.
-
- Supplying PoWa to the extra drive(s) I'll leave to be your headache.
-
- Making internal drives to be df2: and df3: instead of df1: and df2: makes
- sense: Even if you have two extra internal drives, you can connect external
- that becomes df1:.
- If df2: of this hack is ON (JP(DF2) is connected) you MUSTN'T CONNECT MORE
- THAN ONE EXTERNAL DRIVE, because otherways there would be two df2:s of which
- NEITHER would work. In the worst case, Amiga's CIA, Paula or floppy drive(s)
- would get damaged. To prevent this problem, you could cut off signals _SEL2
- and _SEL3 from Amiga's external floppy connector. I didn't do it, I just
- have to remember not to connect too many drives....
- If JP(DF2) is OFF.... Go ahead.
-
- Jumper JP(DF2) selects, if df2: will be reported to be present or not.
- That's because if you build a board for both df2: and df3: and connect only
- df2:, you'd see an icon 'DF3:??????????????????????????????' or something like
- that in Workbench on next bootup.... and lose some valuable CHIP memory.
- Not to mention that horrible waste of time on bootup, when trackdisk.device
- tries to read bootblock from df3:... We're talking about 10 seconds here, man!
-
- What else? Oh, I think I should convince you that this hack is worth building,
- and that it works with me without problems.
-
- Yes, it is and Yes, it does: Look at this:
-
-
- ;------------------
-
- Launched NewShell, process 11
- 11.Ram Disk:> diskchange df3:
- 11.Ram Disk:> df2:1541 DRIVE 3 FILENAME ram:ContentsOfOneC64Disk
- 1541 - Copyright © 1994 by Dan Babcock
- 11.Ram Disk:> getfiles ContentsOfOneC64Disk
- getfiles - Copyright © 1994 by Dan Babcock
- Converting ContentsOfOneC64Disk
- Disk name: DISK 6-SEP-90
- IS THERE A DIFF PRG
- TIME CRYSTALS PRG
- ABSOLUTE DEMO PRG
- PBS DEMO 1 PRG
- LOAD AID PRG
- 11.Ram Disk:> Jeeeee!!!!!!!!!!!!!
- Jeeeee!!!!!!!!!!!!!: ?Redo from start.
- 11.Ram Disk:> ls df0:
- Directory "df0:" on Friday 23-Jun-95
- SCDPlayer11.lha 79643 ----rwed 19-May-89 12:04:43
- YetAnotherCdPlayerV1.1.lha 62578 ----rwed 08-May-94 05:40:43
- : *
- amicdrom.lha 187595 ----rwed 08-May-94 05:42:01
- amicdrom.lha.pi 1234 ----rwed 08-May-94 05:41:31
- AmiCDRomV1.8.lha 108587 ----rwed 12-May-94 21:54:21
- ***Crash! Boom! Bang!
- 5 files - 867 blocks used
- 11.Ram Disk:> ls df1:
- Directory "df1:" on Friday 23-Jun-95
- move.lha 15552 ----rwed 08-May-94 05:57:43
- TrackDiskPrefsV1.0.LHA 22379 ----rwed 26-Jul-94 01:56:01
- : Amiga Users' Fantasy 26-Jul-94 01:54:24
- UND64373.lha 9414 ----rwed 11-Jul-94 01:07:19
- : Extracts/list files in .d64 diskimages
- ***Crash! Boom! Bang!
- 3 files - 97 blocks used
- 11.Ram Disk:> ls df2:
- Directory "df2:" on Friday 23-Jun-95
- libs.info 1249 ----rwed 23-Mar-95 14:27:26
- 1541 17924 ----rwed 17-Jun-94 21:49:56
- 1541.c 14214 ----rwed 17-Jun-94 21:49:12
- 1541.doc 6281 ----rwed 17-Jun-94 14:13:54
- getfiles 9416 ----rwed 17-Jun-94 00:17:48
- getfiles.c 7410 ----rwed 17-Jun-94 00:17:10
- ***Crash! Boom! Bang!
- 6 files - 113 blocks used
- 11.Ram Disk:> ls df3:
- No information for "df3:": not a valid DOS disk
- 11.Ram Disk:>
-
- ;----------
-
- ... so, all four drives were working. Df1: was external. Those strange error
- messages stand for YourFault © Lee Kindness, Scotland. So, I used a 5.25in
- drive to read an C64 floppy.
-
- Only PC makes it possible... NOT! HEHEHEHEHEHE!!!!!!
-
- ;-----------
-
- Possible problems dept.:
-
- I've read that floppy connector's signals should be
- terminated like SCSI bus. I have the cable of about one meter long without
- trouble. If you get occasional read/write errors, terminating could be the
- reason. At least in SCSI bus, terminating problems make ALL devices connected
- to the bus not to work at all or work only whenever phase of the Moon is
- right...
-
- If one or several disk drive's indicator LED lights all the time and the
- drive(s) don't work, some drive has its connector in the wrong way.
-
- Connection of floppy power connector you can find out peeking one of your
- drives.
-
- If your coffee is too hot, you can pour some cold milk in it or let the coffee
- cool down in the cup.
-
- ;----------------
-
- Eh... I haven't mentioned my name, nationality nor address.
-
- Arto Niskanen
- Valtatie 8A8
- 90500 OULU
- ..and that's in FINLAND
-
- E-Mail: archy@maybe.some.day.in.september!!!!!!!!!!
-
-
-
-