Thread

Macintosh Hard Disk 20

68kMLA Software 44 posts Jan 16, 2014 to Jan 21, 2014

#1 Thu, 16 Jan 2014 - 05:56 Macintosh Hard Disk 20 — #1

techknight hooked me up.

would you belive a rat naw'd a hole in the box, and chewed the cord all to hell?

well its true …

anyways i patched it up, and sure enough it still works.

figured i would be funny and try it on my classic II

[attachment=3]Screen Shot 2014-01-16 at 12.45.57 AM.png[/attachment]

[attachment=2]Screen Shot 2014-01-16 at 12.46.22 AM.png[/attachment]

[attachment=1]Screen Shot 2014-01-16 at 12.46.31 AM.png[/attachment]

[attachment=0]Screen Shot 2014-01-16 at 12.47.04 AM.png[/attachment]

would of tried it on the 512k, but after the latest firmware update my floppy emu doesn't work with the 128k / 512k

needed the floppy emu for the HD20 boot disk.

The 5126 portable boots up from the HD20 just fine.

#2 Thu, 16 Jan 2014 - 06:02 Macintosh Hard Disk 20 — #2

I have one of these as well. It was part of a gift from a friend's friend (it came with a Plus), so I was very glad indeed

.

As a bonus, it works perfectly. And the sounds they make are just the neatest, aren't they? A little yellow, but I don't care (might retrobright it sometime, but it blends in okay since it's beige).

Good find!

c

#3 Thu, 16 Jan 2014 - 15:55 Macintosh Hard Disk 20 — #3

would of tried it on the 512k, but after the latest firmware update my floppy emu doesn't work with the 128k / 512k needed the floppy emu for the HD20 boot disk.

Is that expected? I thought it was supposed to work with almost all Macs now? I didn't know BMOW had dropped support for the earlier machines with the latest firmware update. Perhaps you should let him know that you would prefer it if he supported both? And in any case, can't you downgrade it again?

#4 Thu, 16 Jan 2014 - 16:34 Macintosh Hard Disk 20 — #4

It sounds like more of a bug to me. Why would he drop the 512k when he only just now got it working?

Nonetheless, perhaps downgrading to a known good firmware version and getting in touch with BMOW would be a good idea.

c

#5 Thu, 16 Jan 2014 - 18:24 Macintosh Hard Disk 20 — #5

The latest Floppy Emu firmware (1.0L F11) still works on the 128K and 512K - the only change in this version was for LCD contrast adjustment.

That's cool that the Classic II even booted with the HD20. I thought it didn't support it, but I guess it does!

#6 Thu, 16 Jan 2014 - 18:30 Macintosh Hard Disk 20 — #6

ok then maybe my floppy emu has issues then.

yeah it does work with the Classic II… maybe i should try the IIsi as well?

and all the macII line ….

#7 Fri, 17 Jan 2014 - 02:51 Macintosh Hard Disk 20 — #7

Told ya the drive worked ;-)

I got it at the Dayton Hamvention, used it once or twice on my SE to try it out. And it sat.

it also has some type of MIDI player program on there as well.

#8 Fri, 17 Jan 2014 - 03:32 Macintosh Hard Disk 20 — #8

lol i wonder if with a dougg3 rom simm i could add in the HD20 support??????????

then when BMOW gets around to doing the HD20 emu … we could use it with more machines.

#9 Fri, 17 Jan 2014 - 03:46 Macintosh Hard Disk 20 — #9

A rom SIMM for the HD20? Do you mean for the 128 and 512?

#10 Fri, 17 Jan 2014 - 04:37 Macintosh Hard Disk 20 — #10

Apparently, if I read the Wikipedia article correctly, Apple deprecated support for the HD20 in all Macs after the Plus and 512ke (which were the first, and apparently only, Macs to have "official" support), but the ROM drivers were still there on any Mac made since with an external floppy port (SE, SE/30, Performa 200/Classic I/II, and Portable), hence this is why it still works on a Classic II or Portable.

c

#11 Fri, 17 Jan 2014 - 04:49 Macintosh Hard Disk 20 — #11

That's why I don't understand his statement. you need to boot from a floppy on a 512 to be able to use the HD20 and the 128 cant use it, so what would a rom do and for what machine? You need to upgrade the 128 to 512 to use it as far as I know, and If the 512 only needs a KE rom why would we need a dougg3 rom simm?

#12 Fri, 17 Jan 2014 - 07:02 Macintosh Hard Disk 20 — #12

The following Macintosh models have support for the serial (non-SCSI) HD-20 built into ROM

* Macintosh 512Ke

* Macintosh Plus

* Macintosh SE

* Macintosh Classic

* Macintosh Classic II

* Macintosh IIci

* Macintosh Portable

The following Macintosh models do NOT have this support built in:

* Macintosh SE/30

* Macintosh II

* Macintosh IIx

* Macintosh IIcx

* Macintosh IIsi

* Macintosh IIfx

(however maybe support could be added with one of dougg3 roms?)

from this website:

http://www.mac512.com/macwebpages/hd20.htm

#13 Fri, 17 Jan 2014 - 07:33 Macintosh Hard Disk 20 — #13

Have you tried the ones that don't say they are supported? I think I have one under my 30. I'll check. Weird that one version of the II works but the rest don't.

#14 Fri, 17 Jan 2014 - 08:12 Macintosh Hard Disk 20 — #14

Well just to make sure I tried my non scsi version on my II and SE/30 and it didn't work, although I did not try the init. If it allows the 512 to use it I could see if that does the trick. I guess that would be the rom would require to work. Weird they took that out. Maybe the rom was too full?

#15 Fri, 17 Jan 2014 - 17:07 Macintosh Hard Disk 20 — #15

Could you add support for it via Dougg3's ROM?

#16 Fri, 17 Jan 2014 - 17:28 Macintosh Hard Disk 20 — #16

Bbran has to give the thumbs up, if he wants to throw it in and send me the bin I could find out tonight for everyone

#17 Fri, 17 Jan 2014 - 17:54 Macintosh Hard Disk 20 — #17

Well just to make sure I tried my non scsi version on my II and SE/30 and it didn't work, although I did not try the init. If it allows the 512 to use it I could see if that does the trick. I guess that would be the rom would require to work. Weird they took that out. Maybe the rom was too full?

Probably figured SCSI was here to stay and much faster, so why continue support for a slow serial connected device?

Or there was no space in ROM - either reason makes sense

#18 Fri, 17 Jan 2014 - 18:48 Macintosh Hard Disk 20 — #18

- yeah i am sure some will argue the point that its slow and pointless.

but from my experience with Mac OS6 on the HD20, I find it to be fast…

just as fast as your scsi 40/80meggers.

also, where i am going with all of this is…. If we can get HD20 support in the ROM simm….

and if BMOW can figure out how to mount up an boot a Image with the floppy emu, that means you can have one device…

( floppy emu ) with Dougg's ROM simm, That can pretty much do it all.

i mean even the HD20init is on the floppy emu, maybe he can config it so that init hits.. and the HD20 takes over on the same device with the 128k 512k!

I would love to boot a 100-1000meg image from the floppy emu

and be able to run all these machines with it…

it would be extremely convenient!

* Macintosh 128k - init from floopy emu

* Macintosh 512k - init from floopy emu

* Macintosh 512Ke

* Macintosh Plus

* Macintosh SE Dual 800k

* Macintosh SE-FDHD ?

* Macintosh Classic

* Macintosh Classic II

* Macintosh IIci

* Macintosh Portable

* Macintosh SE/30

* Macintosh II

* Macintosh IIx

* Macintosh IIcx

* Macintosh IIsi

* Macintosh IIfx

#19 Fri, 17 Jan 2014 - 19:07 Macintosh Hard Disk 20 — #19

In a way I'm surprised that Apple dropped hardware support for the HD20 so quickly...

Clearly, they never would have sold an HD20 to a customer who intended to use it primarily on a IIsi for example. But what about existing customers moving to new machines? If you had a 512, for instance, with an HD20, then upgraded the 512 to a Plus, upgraded the Plus to 4MB, you would still have had a viable computer when the IIsi came about. Why would Apple not want to make it easy for such a customer to move their data and applications to their shiny new Mac? Just thinking out loud... I guess it points to a ROM size constraint or similar. I can't imagine a commercial reason for the decision to cut out support.

#20 Fri, 17 Jan 2014 - 19:20 Macintosh Hard Disk 20 — #20

In a way I'm surprised that Apple dropped hardware support for the HD20 so quickly... ...what about existing customers moving to new machines?

The HD 20, the external Floppy Port, Floppy Drives themselves, ADB, Serial and SCSI in one fell swoop, Firewire 400, Firewire 800, the 30-pin iDevice connector...

Apple will introduce new technologies and then kill them (sometimes just one generation later) when existing customers "still need" them. This is their S.O.P. They want to sell you a new sprocket to go with your new widget, not a new widget that'll work with your old sprockets.

#21 Fri, 17 Jan 2014 - 19:30 Macintosh Hard Disk 20 — #21

In a way I'm surprised that Apple dropped hardware support for the HD20 so quickly...

I'm not surprised. Apple heavily pushed the Mac Plus upgrade for the Mac 128K/512K in 1988/89 so that they could drop customer support. After promotional discounts, the upgrade was cheap by Apple standards. At the same time, Apple would have dropped support for the HD20.

In reality, "dropping support" meant that they did not test it with newer models. Some models would have been untested for practical reasons (eg the standard Macintosh II does not have an external floppy drive port). Definition of support needs clarification too. Some models will officially boot from the HD20 (ie the Mac ROM was tested to work) and others will read/write (ie boot support was not tested, but may be present in ROM).

Another consideration is that the HD20 has a passthrough floppy port to which a floppy drive or HD20 can be added. That's one more layer of complication for testing...

#22 Fri, 17 Jan 2014 - 20:11 Macintosh Hard Disk 20 — #22

The HD 20, the external Floppy Port, Floppy Drives themselves, ADB, Serial and SCSI in one fell swoop, Firewire 400, Firewire 800, the 30-pin iDevice connector...

Entirely true - maybe this one strikes me as different because it's an "artificial" drop. Had support stopped when the external floppy connector did, that would have been "normal" (regardless of whether external floppy drives might still have been useful at the time). But dropping code out of ROM for a device where the hardware requirements are still met, to me that's a different story.

As an analog, for example: it might be comparable to if, when Apple started selling USB iPods, they dropped the ability to connect a FireWire model to any Mac built after a certain time -- despite having the FW400 port present and having OS and application support still there. It seems arbitrary.

That said, I'm not intimately familiar with the "secret sauce" that enabled the HD20 to function over the floppy port. Is it truly only some code in ROM? As I understand, the HD20 isn't emulating a huge floppy disk, it really is treated differently but happens to use the same physical connector.

In reality, "dropping support" meant that they did not test it with newer models.....

Now that, to me, is entirely reasonable. If that were the case though, I suppose it would have been found to work, at least in part, on some "unsupported" models.

I might test for myself, now I'm intrigued...

#23 Fri, 17 Jan 2014 - 20:50 Macintosh Hard Disk 20 — #23

do you have an HD20 buddy?

#24 Fri, 17 Jan 2014 - 21:09 Macintosh Hard Disk 20 — #24

I have a working HD20, and thanks to you, working SE/30 and IIsi. So I can at least try those out, see what response I get from them, if any.

#25 Fri, 17 Jan 2014 - 21:28 Macintosh Hard Disk 20 — #25

ok cool!

yeah let us know what you find!

looks like the INIT is 28k…. i would think that would fit in the Dougg3's ROM???!??!?!?!?!

if not, then i am sure there is something useless maybe we could trim outta there to make room for this 28k init.

or maybe the SWIM its self wont support the HD20….!?! either way man i would really like to find out!

awesome man… getting some use outta that SE/30

that one was quite a pain in my rear

Glad its working good for you man!

#26 Sat, 18 Jan 2014 - 01:06 Macintosh Hard Disk 20 — #26

ok cool!yeah let us know what you find!

looks like the INIT is 28k…. i would think that would fit in the Dougg3's ROM???!??!?!?!?!

if not, then i am sure there is something useless maybe we could trim outta there to make room for this 28k init.

or maybe the SWIM its self wont support the HD20….!?! either way man i would really like to find out!

awesome man… getting some use outta that SE/30 that one was quite a pain in my rear Glad its working good for you man!

SWIM works. My SE had a SWIM in it, and it booted that HD20.

#27 Sat, 18 Jan 2014 - 01:53 Macintosh Hard Disk 20 — #27

The 30 doesn't boot with the 20 but I have not tried the init. Same with the II's

#28 Sat, 18 Jan 2014 - 08:21 Macintosh Hard Disk 20 — #28

There's a table of what is and isn't supported with the HD20, in the Apple Guide to the Macintosh Family Hardware.

Note: The Apple Hard Disk 20 is an earlier, non-SCSI drive designed for use on classic Macintosh models that have no SCSI port. Although you can connect a Hard Disk 20 to the external SWIM connector of the Macintosh SE/30 and Macintosh IIcx computers, those computers do not have drivers for the Hard Disk 20 in ROM. Neither the Macintosh SE/30 nor the Macintosh IIcx can be started up from a Hard Disk 20. (The Macintosh IIci does have the requisite driver and can start up from a Hard Disk 20.)

Code:

Table 2-1 Non-SCSI disk drives used by Macintosh computers
=============================================================================================================
Computer                    Interface  Internal disk drives  External disk drives         Start up from HD20?
-------------------------------------------------------------------------------------------------------------
Macintosh 128K,             IWM        One 400 KB            400 KB
Macintosh 512k
Macintosh 512K enhanced,    IWM        One 800 KB            400 KB, 800 KB, or HD 20     Yes
Macintosh Plus
Macintosh SE                IWM        One or two 800 KB     400 KB, 800 KB, or HD 20     Yes
Macintosh SE FDHD           SWIM       One or two FDHD       800 KB, FDHD, or HD 20       Yes
Macintosh SE/30             SWIM       One FDHD              800 KB, FDHD, or HD 20       No
Macintosh Portable          SWIM       One or two FDHD       800 KB, FDHD, or HD 20       Yes
Macintosh II                IWM        One or two 800 KB     None
Macintosh IIx               SWIM       One or two FDHD       None
Macintosh IIcx              SWIM       One FDHD              800 KB, FDHD, or HD 20       No
Macintosh IIci              SWIM       One FDHD              800 KB, FDHD, or HD 20       Yes
Macintosh IIfx              SWIM       One or two FDHD       None                         No

#29 Sat, 18 Jan 2014 - 09:04 Macintosh Hard Disk 20 — #29

yeah we need to try the INIT.. on those machines in question.

if they work then we need to try and get that init in one of dougg3's ROMS !!!!

#30 Mon, 20 Jan 2014 - 16:09 Macintosh Hard Disk 20 — #30

Preliminary test results -

SE/30, System 7.0.1: No activity whatsoever. HD20 completely ignored at boot-up and after boot. Tested floppy port with an external 800K drive, the port is fine.

IIsi, Mac OS 7.6: No attempt to boot from HD20, booted from internal HDD. Immediately when Finder loaded, started a desktop rebuild on the HD20. Afterwards, was able to browse the HD20 and copy a file from HD20 to internal HDD.

#31 Mon, 20 Jan 2014 - 16:49 Macintosh Hard Disk 20 — #31

on iisi, go to start up disk, chose hd20 and reboot, then see if it boots?

#32 Mon, 20 Jan 2014 - 18:40 Macintosh Hard Disk 20 — #32

The HD20 INIT is both the driver and the HFS File system driver. If you want "built in" support on a 128k and 512k, just swap in the Macintosh Plus ROMs. As an added bonus, you get 800k drive support.

#33 Mon, 20 Jan 2014 - 18:56 Macintosh Hard Disk 20 — #33

yeah but then the purists get their panties in a bunch.

the floppy emu should take care for the init… then eject… then emulate a HD20, with a 1gig image!

now that sounds fantastic!

#34 Mon, 20 Jan 2014 - 19:14 Macintosh Hard Disk 20 — #34

I never found much "official" info on the topic, but the HD20 does not work at all on the 128k, INIT or no. There just isn't enough memory available.

edit: On further reflection I suppose it is at least theoretically possible that a Plus ROM swap would solve that problem.

#35 Mon, 20 Jan 2014 - 19:21 Macintosh Hard Disk 20 — #35

The HD20 INIT is both the driver and the HFS File system driver. If you want "built in" support on a 128k and 512k, just swap in the Macintosh Plus ROMs. As an added bonus, you get 800k drive support.

It may have been my particular board, but on one 128k board I tried Plus ROMs and it would not work. Checkerboard screen. ROMs were tested just fine. Don't quote me though, I have not tried other ROMs yet. It is something I want to do when I have time.

#36 Mon, 20 Jan 2014 - 19:41 Macintosh Hard Disk 20 — #36

I'v tried plus roms in a 128k,

with different boards in differen instances.. and it always worked… its just STRANGE having a 128Ke!!!

lol

the INIT is 28k.

http://www.mac512.com/macwebpages/hd20.htm

ya i dont get it… this website says this:

The HD20 cannot be used with a Macintosh 128K, the Macintosh 512K can use it once you boot up with the HD20 INIT from a diskette.

but then it says this:

Download the HD20 INIT (28K file)- This lets your old Macintosh 128K or 512K use 800K disks and the HD20 hard disk.

So yeah i don't get it. I guess all there is to do test it first hand.

#37 Tue, 21 Jan 2014 - 02:17 Macintosh Hard Disk 20 — #37

on iisi, go to start up disk, chose hd20 and reboot, then see if it boots?

Done! The IIsi attempts to boot off the HD20. Doesn't get very far, because the HD20 has System 6.0 which doesn't support the IIsi. But it reads, says Welcome to Macintosh, then a polite suggestion to get a newer System and be sure to install support for the IIsi.

Under OS 7.6 I copied some software from the HD20 to the internal disk, and the application runs fine -- so I can be reasonably sure that data copied in that direction is OK. However, I've seen some references to "partial" HD20 support on newer Macs only meant to copy data from, not to, the HD20. I don't really feel like borking a filesystem tonight...

Aside from me feeling a bit risky since HD20s don't grow on trees, the IIsi seems perfectly happy exchanging bits with the HD20.

#38 Tue, 21 Jan 2014 - 05:06 Macintosh Hard Disk 20 — #38

alright lets add the IIsi to the list!

next we should try a SE/30 with a dougg3 rom.

IIcx

SE FDHD

#39 Tue, 21 Jan 2014 - 05:22 Macintosh Hard Disk 20 — #39

SE FDHD work without init. Although accelerator is in it.

#40 Tue, 21 Jan 2014 - 08:41 Macintosh Hard Disk 20 — #40

! have great news… the se/30 boots from the HD20, with Dougg3's ROM simm installed!

#41 Tue, 21 Jan 2014 - 08:54 Macintosh Hard Disk 20 — #41

lol i have great news IIcx boots the HD20 with dougg3's rom simm installed.

#42 Tue, 21 Jan 2014 - 08:58 Macintosh Hard Disk 20 — #42

my hunch is the IIx and IIfx would also boot hd20 with dougg3's rom simm!

obviously it would have to be hooked to the internal floppy connector… no big deal… i have a 2 foot floppy cable hanging out of my MacII for the Floppy Emu already.

as soon as i get my package from olepigeon, I'm going to try and solder a rom simm slot onto the Mac II.. and try dougg3's rom.. i am almost positive it will work.

now all we need is to get a BMOW Floppy Emu … to Emu a HD20 !!

#43 Tue, 21 Jan 2014 - 09:18 Macintosh Hard Disk 20 — #43

Using the HD20 hard drive… I would say its speed is similar to Booting your computer up and running it with an IOMEGA SCSI Zip 100.

I don't find it to be abnormally slow at all… that IWM is working its magic!!!!!

maybe even black magic!

#44 Tue, 21 Jan 2014 - 20:26 Macintosh Hard Disk 20 — #44

Using the HD20 hard drive… I would say its speed is similar to Booting your computer up and running it with an IOMEGA SCSI Zip 100.I don't find it to be abnormally slow at all… that IWM is working its magic!!!!!

maybe even black magic!

It transfers data at effectively 7/8ths * 500kb/s, IE, around 55K/sec. In *theory* the SCSI version of the original ZIP 100 should be capable of bursting around a megabyte a second but the SCSI hardware/driver implementation in early Macs like the Plus is so horrible that the 55K/s from the HD20 is, well, almost in the same ballpark. (A Plus falling downhill with a tailwind can eek around 200-250K/s with a sufficiently fast drive.) If you're running System 6-era programs they're going to be small enough that the speed is going to be "adequate".

For any Mac that *does* have a SCSI port it makes a lot more sense to fit a SCSI->Flash adapter for "production" use; it'll be faster and more likely to be bootable. That said, I'm totally rooting for BMoW or others to reverse engineer HD-20 emulation anyway for use with 512k(e)'s and friends, and there certainly might be some edge cases where it could be useful for data transfer purposes when attaching the device to a newer Mac.

If I had to hazard a guess as to when support for the HD-20 it was pulled completely it's the cutoff between models using the SWIM chip and the SWIM II. See this "what chips are in what Macs" list here. The HD-20 support is in the floppy driver and the SWIM II's drivers are completely different from the SWIM's. (Which means the HD-20 init definitely won't work to add it.) So if you really, really wanted to probe the edges of support you could try cooking up an adaptor from the internal floppy connector to external and hooking the HD-20 up to an LCIII or Quadra (later than the 700 and 900). Pretty sure you'll hit the wall there.