EEVblog #949 - Vintage Australian Made Laptop Teardown - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: November 29, 2016, 02:48:42 am
content: The Dulmont Magnum "Kookaburra" from 1983 is the only laptop to have even been design and made in Australia.Dave teards down this obscure retro classic based on the 80186.

author: Stupid Beard
author_rank: Regular Contributor
timestamp: November 29, 2016, 02:53:42 am
content: That reset button cracks me up. I don't think I've ever seen a reset button as large and easy to accidentally hit as that before. I'd love to know what they were thinking when they came up with that design.

author: kalleboo
author_rank: Regular Contributor
timestamp: November 29, 2016, 02:59:41 am
content: Quote from: Stupid Beard on November 29, 2016, 02:53:42 amClearly their homegrown software needed quick and easy access to resetting a hung machine often...

author: Halcyon
author_rank: Unknown
timestamp: November 29, 2016, 04:12:01 am
content: Dave, would you be able to post copies of the ROM dumps? Perhaps in the supporters lounge? ;-)

author: cdonges
author_rank: Newbie
timestamp: November 29, 2016, 11:54:23 am
content: Quote from: kalleboo on November 29, 2016, 02:59:41 amOhio Scientific 4P had a reset button right next to the enter key. Many tears in primary school...http://www.old-computers.com/museum/computer.asp?c=572&st=1

author: EEVblog
author_rank: Unknown
timestamp: November 29, 2016, 12:22:45 pm
content: Quote from: Halcyon on November 29, 2016, 04:12:01 amWill do.

author: rstanton
author_rank: Newbie
timestamp: November 29, 2016, 02:33:21 pm
content: When Dulmont went belly up, they were taken over by Time Office Computers. I worked on the software for the Kookaburra for about 12 months in 1986/87 before Time Office Computers also went belly up.The use of the 80186 caused some software problems as the interrupt vector table is in low memory and MSDOS expects that to be RAM. When booting the machine, the boot code required interrupt vectors in the same memory space, but in the ROM code. There was a sequence in the code, after MSDOS was loaded into RAM, where the processor was halted briefly while the address lines were swapped between the boot ROM and the static RAM. When it woke up again, it was now executing from the code in RAM at the same address. This required a lot of trust in the prefetch queue for processor code.As you mentioned, the processor was also halted if the software was waiting for a keystroke event.I was working on software drivers for an external RAM disk which was piggy backed onto the machine using that big external bus connector. I don't think it ever got into production and it would have been fearfully expensive as it used large quantities of static RAM. We also had external hard disks and floppy drives connected via that bus for development.Because of the architecture, it required custom software and the world was suddenly being swamped with IBM-PC compatible boxes. It didn't stand a chance, but the concept was good and the software was very professionally written.I think I still have the original source code for MS-DOS 2.11 on a dozen or so floppy disks. I doubt that they are readable now.

author: rrinker
author_rank: Super Contributor
timestamp: November 29, 2016, 03:36:56 pm
content: The Tandy 2000 was a somewhat well-known machine that also used the 80186. It ran MS-DOS but also was not completely compatible with an IBM, although it was MUCH faster and had a much better graphics option with their color video board. At the time, there were some specifically designed software packages for it so you could take advantage of the increased performance and RAM capability compared to the IBM XT. Pretty much the last really decent computer Radio Shack made before switching over to more or less IBM PC clones.

author: Harrkev
author_rank: Contributor
timestamp: November 29, 2016, 08:32:33 pm
content: This is apparently not the first clamshell laptop. The Grid Compass holds that honor. 1982 vintage (designed in 1979). They held the patent on that type of design.https://en.wikipedia.org/wiki/Grid_CompassFrom Wikipedia: "The form factor was first used by the laptop manufacturer GRiD (who had the patents on the idea at the time) for their Compass model in 1982."https://en.wikipedia.org/wiki/Flip_(form)The designer, Terry Crews, went on to play American football, and then started an acting career...https://en.wikipedia.org/wiki/Terry_CrewsYes, I know. Not the same Terry Crews. It's a joke.

author: imidis
author_rank: Frequent Contributor
timestamp: November 29, 2016, 08:56:27 pm
content: Those buttons sure are something!

author: twice11
author_rank: Contributor
timestamp: November 29, 2016, 10:18:41 pm
content: It is the CMOS version of the 80186. That's what the C in the beginning of the model number is for. There even is a CMOS version of the 8086 and 8088. That version is used for example in the Atari Portfolio (another portable MS-DOS compatible computer that lacks IBM PC hardware compatibility). IIRC only the CMOS version of the Intel processors feature a static design and thus are allowed to be clocked down to 0 Hz. So sleeping while waiting for keystrokes would have been impossible to implement using the NMOS 80186.

author: EEVblog
author_rank: Unknown
timestamp: November 29, 2016, 10:22:12 pm
content: Quote from: rstanton on November 29, 2016, 02:33:21 pmAwesome, thanks for joining and sharing that!

author: TheGreatGooglyMoogly
author_rank: Contributor
timestamp: November 29, 2016, 10:25:22 pm
content: The video brought two questions to mind:Is the RAM entirely made of 6264 (8kx8) SRAM? I was under the impression this might be prohibitively expensive, especially in 1984...If the system was designed for battery power, would using LSTTL be detrimental? Or was HCT or HC too expensive to even try in '84.On reason may have been that HCT was introduced in 1982, so availability of various gates may have been an issue. Answering my own question: LSTTL is 2 mW/gate and HCT is 0.5 mW/gate at 1 MHz. So the power savings are not that remarkable.Last thought: this is less a laptop and more a very large PDA, like a Palm Pilot, etc.Great teardown!

author: EEVblog
author_rank: Unknown
timestamp: November 29, 2016, 10:37:38 pm
content: Quote from: EEVblog on November 29, 2016, 12:22:45 pmeevblog.com/files/DulmontMagnumROMs.zip

author: nctnico
author_rank: Super Contributor
timestamp: November 29, 2016, 11:29:21 pm
content: Where is the retro EEVblog intro?edit: It surprises me that the display is still so good. I have a slightly smaller (graphic) LCD display from the same era but it is black around the edges and I have no idea if it still works. I have not turned it on for the past 20 years.

author: EEVblog
author_rank: Unknown
timestamp: November 29, 2016, 11:33:09 pm
content: Quote from: nctnico on November 29, 2016, 11:29:21 pmCompletely forgot!I'll try and add it for next weeks vintage teardown

author: smithnerd
author_rank: Regular Contributor
timestamp: November 30, 2016, 05:44:35 am
content: Interesting hardware. I was surprised to find a 80186 in a Spider Systems SpiderPort RS-232 terminal concentrator. Similar hardware inside; 256K RAM, socketed ROMs for the firmware, though they used Zilog serial port drivers (Z-80 SIO, IIRC).Made in Edinburgh:https://en.wikipedia.org/wiki/Spider_SystemsLast time I switched it on, most of the tantalum caps on the top two interface boards popped, so I'm not sure how many ports actually work now, but it had 10 - with 4 per board, plus 2 on the main system board.

author: mux
author_rank: Regular Contributor
timestamp: November 30, 2016, 10:55:01 am
content: Kinda funny that Dave mentions that these old electronics never really break.In my experience, they're all so incredibly shitty, none of them ever work properly. Quality control and consistent manufacturing were NOT something they did back then. Unseated chips (due to thermal cycling often), tin whiskers, dried out caps, leaking batteries, cracked PCBs (yes, lots of phenolic and paperboard back then), mold and rust damage, cracked brominated PVC, failing carbon contacts... it's all there. And even though the electronics are relatively straightforward and nonintegrated by today's standards, both hardware and software designers often had the most convoluted workarounds and shortcuts to make stuff work, meaning it's still a bitch to reverse engineer if something broke. That includes using unmarked hand-picked transistors with a specific gain to get certain oscillator margins, etc. Not saying it's all like that, but I've seen plenty of bumfuckery in 80s gear. Won't even start about Sinclair...IMO the real golden age for consumer electronics as far as longevity goes, was the early 2000s HP/Dell high-end laptops. Up to 2 years ago I still had an awesome Dell Latitude with 4:3 1600x1200 screen from 2001. Internally, it was impeccable. No mods, all connections were strain relieved, the battery was in its own plastic shell so it wouldn't damage boards when it leaked (and it did - had to replace it), hinges were PTFE/hardened steel based so they will probably last until the end of humanity, even the fan motor had a single-shielded ball bearing. I mean, you would pay the equivalent of $8000 in today's money back then, so that will definitely have had a lot to do with it, but still. No contest.

author: kalleboo
author_rank: Regular Contributor
timestamp: November 30, 2016, 10:57:08 am
content: Quote from: EEVblog on November 29, 2016, 10:37:38 pmStrange, running Strings on these, the text seems mangled and split up. Could the ROMs be byte-interleaved or something? If they were interleaved, I guess I would have expected it to be on the order of bits... (sorry if this is a stupid question, I have precious little experience with hardware in computers older than I am!)QuoteQuote

author: DJohn
author_rank: Regular Contributor
timestamp: November 30, 2016, 11:28:54 am
content: Quote from: kalleboo on November 30, 2016, 10:57:08 amThat's it. The 80186 has a 16 bit bus, and the ROMs are 8 bits wide, so they come in pairs. One holds bits 0-7, the other 8-15. If you take two of the lines you quote:QuoteQuoteand interleave the letters, you get "Use the up and down arrows..."They could have interleaved by bits (or done any other crazy re-arrangement), but splitting the bytes like this makes it easier to prepare the ROMs. You just have to take every other byte, rather than splitting them up into individual bits. It's stretching my memory a bit, but I believe EPROM programming software would often have an option to do this for you.

author: VK3DRB
author_rank: Super Contributor
timestamp: November 30, 2016, 12:44:48 pm
content: Good tear down. I enjoyed it. Many of those chips I remember. Ah, the good old days.The 80186. We build about 200,000 machines in IBM Wangaratta using that processor, in the KDT (Kanji Display Terminal) and project Azalea which was also a dumb Kanji terminal but with a diskette drive. All were exported to Asia - the vast majority to Japan. We also built about 2 million genuine IBM PC's there, from 8086 to Pentiums, as well as Apple power brick processors for the Power Mac, RS/6000 systems and host of other stuff. We made all the motherboards there too. In 1995 we were the biggest exporter in $ terms of non-primary produce in Australia.But I do not recall us ever building laptops in Australia. Dave is right. It is quite likely that it was the only Australian made laptop.Dave should have checked the CR2032 terminal voltage. Probably zero, unless someone had replaced it. A 32 year old battery.

author: Harrkev
author_rank: Contributor
timestamp: November 30, 2016, 03:48:58 pm
content: Quote from: TheGreatGooglyMoogly on November 29, 2016, 10:25:22 pmI first wondered about this. That package is WAY too big to be a DRAM. However, then I realized the truth -- no disk drive at all! No hard drive, no floppy drive. This thing uses a RAM disk, so you are almost forced to use SRAM so that you can have a battery back up.I guess that you could use a battery to power DRAM, but I suspect that would take a lot more power.

author: EEVblog
author_rank: Unknown
timestamp: November 30, 2016, 11:17:20 pm
content: I got a reply from John Blair about this video:Quote

author: Halcyon
author_rank: Unknown
timestamp: December 01, 2016, 12:13:36 am
content: Quote from: EEVblog on November 30, 2016, 11:17:20 pmI have aSharp PC3100in working condition. It's actually a cool little machine and has the best keyboard I've used on a palmtop (the keys are probably 80% of a full sized keyboard's). It has MS-DOS 3.3 in ROM also. Storage was by way of PCMCIA card (battery backed SRAM cards -- I have a whopping 2MB). This did come well after the Kookaburra though.

author: joeqsmith
author_rank: Super Contributor
timestamp: December 01, 2016, 03:03:24 am
content: Thanks for the video. Never would have guessed the 186. I have an old HP computer that looks something like it. Also has DOS in ROM. Looks to be a little smaller. Had the old HPIL serial bus to control my HP meter. Looking forward to seeing the next one you pull out.

author: VK3DRB
author_rank: Super Contributor
timestamp: December 01, 2016, 09:43:35 am
content: Quote from: EEVblog on November 30, 2016, 11:17:20 pmActually it wasn't strictly a PC at the time. It was a clone, or IBM compatible even though it was not IBM compatible or a clone. It is unlikley to have been called a "PC". More likely a microcomputer or something else. I suspect this Aussie made laptop was completely legit, and royalities would have been paid to Microsoft and the BIOS vendor unless they wrote the BIOS themselves.Unlike most of the stuff sold out of the infamous Golden Centre in Hong Kong. The pirated anything and everything. In 1984, I actually saw a clone with the 8 bar logo "IBN" and "Personal Computer". The clone maker's name was "Improved Business Nohow". Well, they didn't "nohow" to spell but they certainly "newhow" to pirate intellectual property. Oddly enough its address isFuk WaSt., Sham Shui Po, Hong Kong. The street might have been was named after the sounds heard when another raid was about to occur on the Golden Centre..In 1984, Golden Centre was the world's biggest pirate centre of PC AND mainframe software according to The Bulletin magazine. Anyone who visited the Golden Centre in the 80's would certainly remember the roaring trade in pirated software and cheap hardware. I was there in 1984, and I never saw any machine sold that even resembled this innovative Aussie made "laptop PC". I bought a "rotten Apple" there. If I were smart, I would have bought shares in rotten Apple instead.

author: kalleboo
author_rank: Regular Contributor
timestamp: December 03, 2016, 08:43:12 am
content: Quote from: EEVblog on November 29, 2016, 10:37:38 pmThanks to your ROMs, the machine is now up and running in the MAME emulatorhttp://forums.bannister.org/ubbthreads.php?ubb=showflat&Number=44666&page=483

author: EEVblog
author_rank: Unknown
timestamp: December 03, 2016, 10:57:38 am
content: Quote from: kalleboo on December 03, 2016, 08:43:12 amSweet!

author: twice11
author_rank: Contributor
timestamp: December 05, 2016, 08:16:14 pm
content: Quote from: twice11 on November 29, 2016, 10:18:41 pmThis is complete bullshit. I am kind of disappointed to not being called out on this. The C80186 is an NMOS processor, specified at a maximum dissipation of 3 Watts and a clock frequency between 2MHz and 8MHz (seehttp://www.cpu-world.com/CPUs/80186/Intel-C80186.html). I could not find any 80C186 (the real CMOS editions) dating before 1987 on cpu-world.com, so the Kookaburra likely was too early to use a 80C186 (and other CMOS processors might have been too expensive indeed).Quote from: twice11 on November 29, 2016, 10:18:41 pmThis still stands. The portfolio dates to 1989, so a CMOS version of the 8088 was available. Also the clockability to 0 only for CMOS is confirmed by cpu-world.com (it wouldn't make much sense on NMOS, as NMOS consumption doesn't drop to (nearly) zero without a clock). The Kookaburra thus most likely powered the processor off hard, and hat to reset it on every keystroke (with the RAM being static, resetting the processor does not incur rebooting the operating system). You are likely to find a special reset path in the ROM dumps provided here to wake up the system on an external event like a key press.