You set both the HDD and FDD to the same LUN near the end, you can see both access LEDs going on/off simultaneously. Give it another go, they need to be on different LUNs.

@kotto7877

2 жыл бұрын

@@fffUUUUUU Jealous much?

@MrLukealbanese

2 жыл бұрын

@@fffUUUUUU he is in fact a professional computer dude. He also has a computer Science degree which he studied like 30 years ago.

@stonent

2 жыл бұрын

He's the head IT Security at a large company.

@8o86

2 жыл бұрын

Also, regularly points out that he's not a pro, just having fun.

At the end of the 80ies I read an article about how easy it was to connect "PC" harddisks to my Amiga 500. One would need an OMTI-MFM-Controller (it was a newer model, perhaps a 5520?) plus a few TTL ICs to interface it to the expansion port and then simply add an MFM drive to it. I followed the instructions to the letter and got the cheapest HD I could find (still expensive!), which indeed was an ST-225. This worked on the first try (I don't remember the exact procedure, though) and compared to floppy disks this was heaven! The only problem was a big one in my book, though: Many games couldn't be installed on this drive, including my beloved Ultima 5. I had to swap disks like in the C64 days which annoyed me to no end. About a year later I converted to PCs and never looked back.

This is literally how the earliest SASI and SCSI controllers worked, you bolted them onto existing ST506 (or even 8 inch SA1000) drives.

Cool! A Seagate ST225! I used one of these in my first PC back in 1988. I hooked it up to an RLL controller instead of a MFM, and due to the increased sectors per track (26 instead of 17) I got a whopping 30MB. It worked fine for as long as I had the machine. I am surprised you actually got one that is still alive after all these years.

@mal2ksc

2 жыл бұрын

The only difference between the ST-225 and the ST-238R was that Seagate guaranteed the ST-238R would work on a 2,7 RLL controller. But I never saw an ST-225 that didn't work, unless it was broken in general.

Scientific Micro Systems had some interesting products back then. They were the first company to design and produce a single-chip ST506/412 disk controller, and their single-chip RLL controller was a very popular solution back in the mid-to-late 1980s.

I had a couple similar ones (no floppy though) that I got at an auction. You want to do this on an Amiga with a 2091 card. The Amiga's Mountlist capability was extremely flexible. You could arbitrarily specify disk geometry and file systems. It was also LUN-aware. If you got the parameters right, it does work.

I won a 10M hard drive package for the Amiga at a Conference in the mid maybe late 80's, it turned out to be an MFM drive with a card similar to this that converted it to SCSI. Wasn't this card I don't think, as I think it was only a single one to one to convert a single MFM drive to SCSI but pretty neat to see this.

@Okurka.

2 жыл бұрын

Definitely not mid 80s.

I have a Sun-2/120 server that uses the Adaptec ACB-4000 version of this card (no floppy). The SunOS system supports it directly. These servers were in the $50K range, new (early 80's). These controllers allowed the server to use the new 5-1/4" micro hard disk drives internally. Otherwise they use external 8" SMD hard disks (with case and power, about the size of carry-on-luggage). Modern SCSI disks were rather new and not used yet. These SCSI adapter cards existed for ESDI, MFM, and QIC tape drives. I don't remember them being used on PC's or Macs of the era as you could get cheaper ISA MFM controllers and real SCSI disks.

@TimSedlmeyer

2 жыл бұрын

I sent in this card and according to the ebay seller the drive it was attached to came out of a 286 system. Why one would use one with a 286 system I have no idea but evidently it was.

@JVHShack

2 жыл бұрын

I'd really like to reverse engineer that Adaptec ACB-4000 for the pile of Zenith SupersPort laptops that I have so that I can connect a modern drive solution to them in place of the original 26-pin JVC type MFM drive. I know of the DREM drive emulator, but that thing costs $300 per unit. That's not feasible for me when I have 6 of those laptops that work.

@foobar1979

2 жыл бұрын

I'd love to see a video of that sun2/120 if you still have it.

I am almost positive a manufacturer would have sold a stand alone unit as a complete external drive. There was a similar unit available for the C64 called the Lt. Kernal that contained a MFM drive and controller.

You had a question on an earlier episode about sasi and scsi the main difference between the 2 is the second letter in one is an "a" and in the other is a "c" quote from wiki is "Until at least February 1982, ANSI developed the specification as "SASI" and "Shugart Associates System Interface"[7] however, the committee documenting the standard would not allow it to be named after a company. Almost a full day was devoted to agreeing to name the standard "Small Computer System Interface", which Boucher intended to be pronounced "sexy", but ENDL's[8] Dal Allan pronounced the new acronym as "scuzzy" and that stuck.[5]"

@nickwallette6201

2 жыл бұрын

Oh man, that is pure cringe. ;-)

Thanks for the good long form content, it’s stuff I like and also helps my anxiety.

Franken floppy!! 😁 Never a dull moment in the basement. Fun experiments there Adrian! Looking forward to the next video.

These SCSI to MFM / floppy adapter boards were used in non-PC applications in the 80s and early 90s. As Andrew Lindh mentioned earlier, SUN was using a similar adapter for the low-end SUN2 workstations. But the official Acorn hard disk drive for the BBC microcomputer included an MFM drive and an Adaptec SCSI to MFM adapter (as well as an Acorn SCSI to 1MHz bus converter board). Finally my HP R/384 instrumentation controller has a floppy drive which is connected to the SCSI bus via a Teac FC-1 SCSI to floppy (no hard drive) adapter.

OMG the sound difference when you powered everything off. I remember that sensation. Not realizing just how LOUD everything is until it's poweredoff.

Brilliant, I was laughing out loud through much of this. What a great video, thanks Adrian.

Re: the Z8 processor on this board, the *only* similarity between this and the Z80 is that they're both designed and manufactured by Zilog. Whereas the Z80 was designed as a general purpose CPU, the Z8 is optimised for control applications. The Z8 could be equipped with 2K or 4K of ROM, contains 144 internal registers (124 of which are general purpose registers arranged in switchable banks), 4 8-bit I/O ports, programmable counters/timers and a UART for serial comms. It is also designed around the Harvard architecture and has seperate memory banks (of up to 64K each) for program and data storage. I used the Z8 extensively in the late '80s/early '90s and it was a fantastic processor for control applications. You wouldn't want to try and build a general purpose computer around one though.

@jaymartinmobile

2 жыл бұрын

I disagree with the "general purpose" computer comment. There were a number of Z8 and later the S8 (Super 8) processors that had a form of BASIC built into them and the Z8 series had such things as a quazi-static RAM support chip that hooked up with minimal effort. Adrian had one of those QSRAM's in one of his mail-call's not long ago but wasn't sure what it was. With the BASIC version of the chip, a QSRAM, and a handful of support chips you could build a pretty decent running 8/16bit computer. Radio Electronics even had a build article for one. Sure it wasn't a commodore 64 or anything and the BASIC was mostly Tiny BASIC with extensions but it played the old Star Trek or Swarms text-ish based games quite well.

@ensor2872

2 жыл бұрын

​@@jaymartinmobile Yeesss, you realise that just because it's possible to insert your wedding tackle into a blender and press the "on" button it's still a damn fool idea!? The Z8 was designed from the ground up to be a microcontroller, thus its architecture and instruction set are *heavily* tailored to that function. Yes, you can still build a general purpose machine around it but any such design would be inelegant and compromised by the architecture of the CPU. For example, the Z8 cannot directly address a particulat byte in memory, all such accesses have to be performed indirectly using a register pair as a pointer. That may not sound like a big deal, but along with other optimisations to make it a great MCU, these things make it a very sub-optimal CPU for general purpose tasks. And have you ever used a Z8 system running the built in BASIC? A couple of the very earliest systems designed and sold by the company I worked for designing Z8 based systems were based on that version of the Z8...slow doesn't even begin to describe their glacial processing speed. I guess what I'm saying boils down to "the right tool for the right job".

I think we all liked SCSI for many reasons, except for the price tag. It always was substantially more expensive than a similar HDD which you would throw into the average PC. The other annoyance was the fact, that the capacity of SCSI drives always lagged behind those of the IDE HDDs. I remember well that at the time the first 1GB IDE drives were available, the biggest SCSI drive I could buy was a 512 MB and it cost the same as the bigger IDE. Understandable that there were interfaces like the one you have shown.

Embedding an OMTI PCB with some bus interfacing GALs was the go-to-solution for the first aftermarket A2000 HDD kits.

Z8 is not related to the Z80. The Z8 is a MCU that's very different than the Z80. Zilog still makes the Z8 chips (newer and faster).

@Torbjorn.Lindgren

2 жыл бұрын

Yeah, I check some Z8 assembler and while some of the opcodes looks somewhat familiar (IE Zilog style) the register set is clearly WILDLY different. And Wikipedia says it's a modified Harvard architecture so internally it's very different on the most fundamental level.

@squirlmy

2 жыл бұрын

that's not very logical, though. They just named all their chips Z8*****whatever???

@proCaylak

2 жыл бұрын

@@squirlmy think about intel 8080 and 8086. they are numbered similarly, but they are entirely different. like, no backwards compatibility at all.

@proCaylak

2 жыл бұрын

@@fffUUUUUU still, no backwards compatibility compared to 286, pentium etc.

Came across this card in a huge box that had enough space for two massive MFM drives but only one was populated and had two 5inch floppy drives. It was connected to a system running AT&T Unix.

7:45 the answer is yes. I had a Columbia (XT clone) and the ST-506/410 actually had the Adaptec version of that board screwed right on to the bottom of the drive. The Colombia was SCSI only and configured for multiple discs to run a BBS. So at least in OEM config, Colombia shipped this board, or a, functional cousin, with some of their systems. One thing I DO remember about these boards is that they are SUPER sensitive to termination. Termination, at least in those days, was more of a dark art than a science. The science is the "official" documentation telling you what to do. The dark art is doing insane weird termination configurations with multiple drives and non-disc devices (scanners, printers, etc.) to get everything on the chain to recognize.

@jurgmesser7723

2 жыл бұрын

Actually, I remember the termination problems the other way round, that it became more difficult in time. In the beginning, you had either a prominent terminator plug at the end of your daisy chain or you had installed 3 in-line resistor packs on your last device. Later you had just a jumper to switch the termination on/off for the drive. This was easily overlooked, especially when these jumpers became the size of half a rice grain and were hidden amongst some more jumpers for other functions. 😄

An Interleave of 1 may be why the drive was so slow to read and write. 3 would be safer on hardware of that age, and it might even be 4.

@GodmanchesterGoblin

2 жыл бұрын

I thought the same. Not many know about those details these days.

@kaitlyn__L

2 жыл бұрын

@@GodmanchesterGoblin although there’s an older video on this channel demonstrating exactly that. I believe it was an early Compaq. IIRC in a 486 test machine with a faster controller the drive didn’t need an interleave, but on the older Compaq it needed 3 or 4.

@GodmanchesterGoblin

2 жыл бұрын

@@kaitlyn__L Interesting stuff! Back in the 80s I designed a couple of ST506 compatible disk controllers and device driver software for a proprietary computer system. The 1985 version worked with an interleave of 3, the 1988 version worked with an interleave of 1. It was so much faster.

A long time back, I had a similar board I bought from a local surplus dealer. It was described as a SASI interface (Shugart Associates System Interface), not SCSI. I connected to an Amiga with a scsi interface, and it worked. I recall similar documentation with all the commands and such. fun. sort of. also. I had the idea that the "floppy" interface was actually for some sort of tape drive. I don't recall the details on why.

Reminds me of the Atari Megafile, for the ST line. Was also a MFM or RLL drive with some translator logic for ASCI.

@ensor2872

2 жыл бұрын

First hard drive I ever bought was an Atari SH204 20MB "shoebox". Inside was a 20MB MFM drive (ST-225 if I remember correctly) connected to an Adaptec SCSI to MFM controller similar to the one which is the subject of this video. There was a small card with a few TTL chips on it which converted the ST's ACSI interface to full SCSI for the Adaptec board as the differences were relatively trivial. The Megafiles were very similar, except that the Adaptec board and ACSI-SCSI converter were integrated into a single controller board which could handle both MFM and RLL drives depending on how they were configured.

This device looks familiar to me. I used a Western Digital WD 1002 adapter long ago to connect a Miniscribe MFM-drive to a self-build CP/M system with an also self-build SCSI adapter.

I remember having an ICL SCSI external 30M hdd which when I took it appart contained an MFM HDD and a converter PCB. I remember using it on an Atari ST

They made tons of stuff that used SCSI as an interface protocol! I have a QTV teleprompter card that talks to the computer via SCSI, and it outputs NTSC video teleprompter screen. It also has a scroll wheel with story up and down buttons!

20:49 you should be able to read FAT-12 disks with the appropriate extension in System 7. Also the Apple File Exchange app should be able to read FAT-12 as well.

2:27 The HY6116 is a bog-standard 2K static RAM, not flash memory.

10:04 IIRC multiple LUNs were how it handled some HD partitioning schemes. Anyway I remember it being able to work with multiple LUNs with relative ease.

I do remember those old St-225 hard drives.

This board is definitely more useful than the MFM to IDE board that I have, so you can hook up an MFM drive to an IDE controller.

I resurrected a "3COM 3server" in the late '80s which I acquired at work. It was intended to act as an ethernet file server for a workgroup of PCs running DOS. Internally it had a large processor board with an Intel 80186, somewhere between 2 and 8 MB of soldered-in SIPP-type RAM and it ran on 3COM's proprietary version of DOS 3.1 (details are getting hazy here, may have been DOS 2.x). The processor had no controls other than a mode selector which was used to configure it while using one client PC and management software. The processor connected to a second enclosure over SCSI-1 containing an OMPTI, a Micropolis 70MB MFM full height drive and a power supply. I couldn't get it working for some reason related to the older DOS version it expected. In the end I abandoned the 3server and just used the box that included the OMPTI and MFM drive. I added a 2nd native SCSI disk to the box and connected all that to an IBM AT running DOS 3.3 via a SCSI card which I recall was a generic one using an NCR chipset. It worked just fine booting off the native SCSI drive and I never had to delve into the OMPTI for configuration of the MFM drive, noting that pre-www I had no easy way to find documentation. The OMPTI-hosted drive partitioned, formatted and appeared the same as the other SCSI fixed disk. I set up the AT up as a Lantastic peer-to-peer 10Mbps network for our engineering workgroup and that worked very well. (I can't say enough about the high quality of then-contemporary Lantastic hardware, software and documentation.) As regards using it with a Mac, it should appear as a SCSI block device and be partitionable and formattable with the normal Mac utility, altered of course to accept non-Apple drives. SCSI was pretty solid even in those days and if there's an issue it'll be on the Mac side. There should be no "drivers" required.

You either got the Floppy and the HDD on the same LUN or the Mac doesn't support multiple LUN on the SCSI bus.

I have a similar SCSI controller paired with a 60mb RLL drive in my Lisa. It was part of a SuperMac DataFrame. They were targeted at Macs! The hard drive settings are actually stored on the hard disk itself.

I have not seen these ever attached to a PC. In there day they were known to be supremely reliable and I have never heard of one failing in the field.

The mismatch in the track count is likely due to the controller board reserving a number of tracks as spares. On detection of a bad sector during format that sector will be transparently remapped to the spare pool. Likewise a sector that fails during normal operation can be transparently redirected to the spare pool on write.

Adrian: I know this comes a bit late but I just heard about the BlueSCSI project which might be interesting for all the people who have a computer that uses SCSI drives. It's a modern SCSI to SD bridge that supports drive images on the card. That way you can make a bunch of drive images on a PC and just move them to the card. The device is quite cheap and available as both an internal card or a dongle.

Interesting device, couldn be fun seeing it tested on other SCSI-equipped systems too, assuming software is made available... :D

I'm pretty sure that I bought a SCSI hard drive back in the day with one of these boards on it. It was an ancient 20 or 30 MB (I don't remember exactly) drive that also had an integrated tape backup unit in the same case. The whole unit was FREAKING HUGE! I remember having to take it over to a friend's house to fix it, and when he cracked it open, he said something like "huh... that isn't a SCSI drive..." Turns out it was a 5.25" half height MFM hard drive (it might have even been a ST-225) with one of these boards screwed onto it. The tape drive portion of the unit was a standard SCSI tape drive tho.

Is it me or does that big ol' Seagate drive sound a bit like bagpipes being played from far away? So great to see LaCie's SilverLining software in action again. Takes me back with a lot of great memories.

MFM over SCSI? It'd be interesting to see if that could work when paired with a much more modern computer! Imagine seeing that ST-225 showing up on Windows 10!

@rawr51919

2 жыл бұрын

Windows 11 even

@squirlmy

2 жыл бұрын

SATA is based on SCSI, so I wouldn't be too surprised. There were Adaptec ACB-4000 and Xebec 1410 that were other SCSI "bridgeboards". Back when I've considered trying to hook up old MFM-RLL drives without SCSI, I got stuck at not having ISA interface slot. You're dealing with less abstraction, software drivers for harddives didn't even exist until 2000, so... Also, what are you going to do with really, really slow 20MB of disk?

@proCaylak

2 жыл бұрын

@@squirlmy I'm guessing, things like archival stuff or copying files directly to that hard drive for using it on an ancient computer without bothering with floppy disks/networking and so on. I know that more modern and more convenient solutions exist for fixed storage on ancient PCs. No need to tell me about that.

@ensor2872

2 жыл бұрын

@@squirlmy SATA is not in any way, shape or form based on SCSI. You're confusing SATA with SAS, which is *S*erial *A*ttached *S*CSI.

@kaitlyn__L

2 жыл бұрын

@@ensor2872 but the SATA protocol was based on SCSI, hence on *nix SATA is sda1, sda2, etc just like SCSI, compared to ada1, ada2, etc for IDE drives.

I have a couple OMTI 7200's (same form factor as your 5200). Didn't get any disks with mine. I do have an OMTI 8240 that came with a disk labeled "OMTI Formatter".. But, the 8240 is a completely different beast -- it's an ISA card that is just more like an MFM + Floppy interface.. Not a SCSI bridge.

Is essence, _everything_ SCSI was an embedded computer hanging off of whatever the "proper" device was. This is why SCSI stuff was reliably more expensive than e.g. IDE.

Omti had a lot of very niche products for late 1980ies computers.

Hmm the Chips&tech one seems to be for DMA: 82C5060D : 4 channels DMA controller But there are some SCSI stuff in their 1990 catalog… 82C5058A - Single chip SCSI controller 82C5080C SCSI multifunction device

The light on the hard drive came on at the same time as the floppy. Can the floppy be set up as another scsi id.

Hi Adrian, hope you are well, i found this description of a Supermac old util that might be of some use: SuperMac Dataframe Manager v4.1e (96 k) This utility is useful for anyone who owns a Supermac DataFrame hard drive. These external drives were actually old MFM drives connected to a SCSI converter board for use with the Macintosh. Manager is the only way to format, test, or change the SCSI ID of the drive (no switch-selectable SCSI ID on these!) If you cant find this util, i can send you a copy. Best Regards.

My first PC (Compaq Deskpro 2000) that I got (in 1986) had an ST-225 in it. I remember the FAT16 formatted capacity was 21.2MB. So something is definitely askew, and it's likely it was the Macintosh itself. Apple has never been big on users attaching their own items to its' products. (The main reason, I believe, why Apple almost never followed standards completely, but always added something that would render their devices useless on a PC, or vice versa.)

Cound there be some sort of software/firmware on the card itself like with old PC hard drive controllers -- the ones you had to use 'g xxxx' in debug to start...

The low write speed may be due to read after write verify being enabled.

I think the ST-225 is my favorite MFM hard drive.

There was a Tool for MacOS to send custom, commands over SCSI, but i don't know the Name anymore. I used it to init a special image scanner.

Ive seen a few of those back in the day. I tried them on PCs but never got any of them to work. I never had a mac to try it on.

I need one of those type of boards that will allow 2 IDE to connect to the SCSI to run internal IDE rather than SCSI.

Actually, Zilog made a micro controller called the Z8, and I think that's what you got on the board.

@douro20

2 жыл бұрын

Z8 microcontrollers are still in production, including an enhanced version called the Encore!. There was also a DSP enhanced version which found use in some IDE hard disks. Perhaps the most widespread application of the Z8 is in TI graphic calculators.

@oldguy9051

2 жыл бұрын

Yes, and it's the ROM-less version as indicated on the chip where you use an EPROM or PROM that you can easily replace.

@scharkalvin

2 жыл бұрын

@@oldguy9051 Both Zilog and Intel made romless versions of their micro controlers (8051/8031, etc). But these weren't really romless. They were actually mask rom parts, with the WRONG stuff in the rom. Perhaps the mask was done wrong, or the customer changed their mind. In any case, if you strapped a pin you could disable the rom and connect an external one. Intel sold the 8051 under the part number 8031 when it was romless, but there was actually a rom inside that would be connected if you didn't tie the right pin to the inactive state. I guess they could have put the strap inside of the chip (and maybe Zilog did).

@adriansdigitalbasement2

2 жыл бұрын

Ah I see -- some versions had the ROM internal to the DIP package, like the 8051. Makes sense.

@oldguy9051

2 жыл бұрын

@@scharkalvin Didn't know that! Thanks!

Look at the date codes on those chips... I see several from mid/late 93, the board was probably put together at the beginning of 94 and then finally put on sale. Isn't that quite late for such a MFM contraption?

@GodmanchesterGoblin

2 жыл бұрын

It's at the back end of the MFM and RLL era. IDE was just taking off in the early 1990s, and ESDI was already used for larger drives. My guess is that board could be one of the last one's of its type.

Maybe you could try this mfm to scsi adapter with your mfm hdd emulator you have showed 3 months ago in the other channel?

I would have bet my allowance that that wouldn't have worked at all. Amazing.

Hi Adrian, I notice that you had the board on your anti static pad. Is the pad conductive? could it possibly short pins on a board resting on it ?

@adriansdigitalbasement2

2 жыл бұрын

The anti-static pads have a meg-ohm resistance, so even if they were making contact, it won't have any effect on digital electronics. (Could have some kind of effect on super sensitive analog stuff)

Maybe better luck by using an PC with an Adaptec 1542CF and then adaptec EZ-scsi untils and/or CorelScsi utils. i think that there will be lowlevel applications to better control it and format the drives

Maybe it was for an IBM compatible with a SCSI interface.

DIY Twiggy Mac, let's goooo :D

@adriansdigitalbasement2

2 жыл бұрын

Haha maybe the old code is lurking in the ROMs somewhere for that :-)

You might get better performance by formatting with a higher interleave (probably 4 or 6)

@stonent

2 жыл бұрын

Yeah I was thinking an interleave of 1 was a bit aggressive.

Super mini mail call. Almost forgot where I was............. Hit the bong and going to the basement and install stacker on the MFM -G=C800:5

DEC used these as did sone early VME systems

An useless bit of Mac-related trivia relating to that Zilog MCU is that the drive inside the original Apple HD20 (the one that connects to the floppy port) has one of those on its PCB, but it's one of the versions with a built-in ROM.

@adriansdigitalbasement2

2 жыл бұрын

Oh fascinating! If those drives die, does the HD20 controller work on some other drive?

@Zeem4

2 жыл бұрын

@@adriansdigitalbasement2 Not as far as I know, the drive appears to have a unique interface. Mine had been intentionally damaged inside when I got it, so I kept the case with the power supply just in case I ever decided to put a Floppy Emu or a SCSI2SD inside it.

imagine having an external HDD that's bigger than the computer itself

Z8 is a romless MCU based around the z80 architecture iirc.

@lindoran

2 жыл бұрын

I stand corrected.. it is a different instructions set entirety.

Shoulda used Hard Disk Toolkit 3.0

C'mon man! This is jumping the Macshark :)

You know you have to try an 8” floppy drive now.

Confuse-a-Mac. (See Monty Python's Confuse a Cat skit)

use a mfm hard drive with windows xp vita and win 10 pro as external storage

somehow I got unsubscrbed to your channel! But still in my reccommended list??? idk what happened but resubscribed! Love your content!

Imagine a 360KB floppy based hard drive 🤣

Red Rock Technologies.

0:15 missed opportunity for "Hi to all my Virgin viewers!". :-)

Wouldn't call working mfm drives cheap anymore

I think i have such a thing? Hmmmmmm....

Oy vey! That green CRT in the Mac is just wrong...

@stonent

2 жыл бұрын

I think its a bit heard to read from a distance for us.