stevenh « modelrail.otenko

9Nov/160

Installing an AT Motherboard in an ATX Case

I needed an AT case for this naked 386 AT motherboard and hadn't had much luck searching eBay. Little did I realise that I could put the motherboard into an ATX case with minor effort. All AT cases on eBay were way out of the price range, so I went back to the store that I purchased the power supply from for the Compaq and came back with another bargain!

There seems to be a faceplate missing, but I can't complain since I got it for AUD$20. It didn't come with a power supply, so I chose to use the AT that the motherboard came with. Of course, the first problem (it's still a problem, actually) is that the power switches aren't able to be swapped. ATX uses a 'soft power' switch whereas AT runs the full 240v right up to the mechanical switch to control the power feed. This is still currently hanging out the side of the case.

Mounting the motherboard was easy enough. Turns out that the read plate actually has all the required markings for the AT motherboard spacers!

A bag of goodies was included and I quickly got the motherboard into position.

Before going any further, I realised that I'd not put a new battery on the board yet. I cleaned the remnants of the previously leaky battery and mounted a coin-cell holder.

Once screwed down, everything fit back into the case perfectly.

The majority of front-panel wires were still compatible with the old AT style pinout... I just required a quick google to find information on the AT System panel connector.

Of course, the included I/O Panel doesn't fit an AT motherboard, so there's extra ventilation at the back. There seems to be all sorts of hints online to make your own plate, but nothing off-the-shelf that I could find.

I popped the top off to see if I could mount the power switch but there was no room for it. I'll have to work out a better mount for it, as the current answer is to have it hanging out the rear.

After purchasing a PS/2 to AT-style keyboard converter, I was able to actually boot the thing up! Now to get some software onto it...

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2Nov/160

Melbourne – Cup Day 2016

Usually public holidays means very little freight traffic, but everything-and-more was running yesterday! I promised myself to sit in front of the computer, and work on computer-related-projects, but gave up quickly when I looked at the radar and saw that XR554 was leading the Long Island. I ran out of the apartment and just managed to catch the Metro Frankston train in front of the freighter from Hawksburn Station.

Glenhuntly Station - Long Island Steel Train

Glenhuntly Station was chosen as the vantage point. I'd always wanted a shot of the steelie coming round the bend. This intersection happens to be a 'Tram Square' where tram lines cross the railway lines. The catenary has to cross at this point too, and so only one network is energised at a time. There are insulators isolating the crossing wires and, I would assume, there is some large electrical switch that chooses which network is powered into the junction.

I was paying too much attention to the infrastructure and nearly didn't hear the freighter approaching!

The sun came out perfectly for the curve. Very happy to see an XR in the lead.

Two 49s and a Tamper

I was about to head home, and continue that work I promised myself, when saw something strange on the radar. A 49 Class NSW Locomotive heading south into Melbourne. These are sorta like the Victorian T Class, and aren't often down south. Not really knowing a good location, I attempted somewhere new, on-foot. From Albion Station on the Subury Line, I walked over to the curve where the Standard Gauge joins (or re-joins, really) the electrified broad gauge.

Turned out to be a pretty good location! One other on-looker had already been waiting there too. The colour-scheme looks really good on this loco, especially in overcast lighting.

CSR002 - The Sugar Cube

The map indicated that the new SCT movement was coming through next. It wasn't for about an hour though, so I caught the train back to Sunshine and got lunch at the mall. I also purchased an external battery pack for my phone, as the radar does happily trash one's battery. These batteries usually come pre-charged and this brick happily gave me a full charge prior to giving up the ghost. After mucking around and not paying attention to the radar, I realised that I was now running late and that CSR002 was already at Jacana. A quick run from the mall straight to the overpass saw me back in location with around 1 minute to spare.

These sugar cubes get their name from their very boxy shape, and the fact that their class name is 'CSR' (a famous Australian sugar company.) The train hurtled round the bend with 2 vans which it had retrieved from the new SCT depot in Wodonga.

The 49s return home

These two didn't hang around long. After the CSR came through, I ventured back to Albion station and awaited the next Metro train. I just missed one and so the next service wasn't for ~20mins. This was fortunate as the 49s showed up on the radar on the triangle near the LPC in Dynon. It turns out that they were turning around on the triangle; I assume 4911 has the accreditation to run in VIC and 4917 was there as backup.

They bolted through at track-speed and headed home. It always seems to be the days you least expect that provide the most excitement.

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31Oct/160

Steamrail – 50 Years Of The Vintage Train

Steamrail Victoria is a heritage train preservation group that runs out of the Newport workshops, Victoria. They have a large selection of operational vehicles and they run a lot of tours throughout the year in Victoria.

This past weekend they ran a 50th anniversary for their "The Vintage Train" service that commemorates 50 years of running preserved steam locomotives in Victoria. They outdid themselves by having two consists running from Melbourne to Geelong, in parallel where possible!

Getting the consists to Southern Cross

As that there is no turn-around facilities at Southern Cross Station, both locomotives had to run tender-first with their consists from Newport to Southern Cross.

R761 was up first, basking in the morning sunlight through Spotswood.

D3-693 came through a few minutes later, letting a spark run first.

Southern Cross to Geelong

Both consists left Southern cross just after 10am. Initially it was stated that one was to run via Werribee and the other via the Regional Rail Link. I'm still not sure why, but both ended up running via the RRL. I caught R761 at Tarneit on the curve I previously mentioned. The train perfectly ploughed into the sunlight just as it approached Tarneit.

Following Google Maps, I then proceeded to Manor Loop. There was an intention to beat R761 to this location, but that wasn't an option obeying traffic rules. Instead, D3693 came bolting down the RRL as it joined back onto the Western Line. This was an unexpected delight, as it was actually meant to have run via Werribee?

From here, I joined the cavalcade. Turns out there were a lot of enthusiasts on the road. Of course, these were back roads and one or two of them were dirt. Unfortunately, the enthusiasts have passion and had no regard for road rules. Rocks were flying, dangerous overtaking was being practised and the poor locals really had no idea what was going on as an army of bad drivers plundered their way from Little River to Lara.

I attempted a few shots along the way, but the trains were, for the most part, well ahead of me. The sun was also in a bad spot. To make things harder, the trains were also leap-frogging for front place and my timing sucked. There was also a serious amount of contention for 'being in front' when a good photo spot was popular.

I then took my time, there were no more locations to get the trains before Geelong.

Geelong Station

Both trains were already on the platforms and one loco had already started the run-around. There was also a crowd who must have heard the trains arrive as they didn't seem to know what the trains were actually doing.

Both trains ran around. I assume they then went off to the V/Line depot and turned on the turntable. The goal was to then bring them back into the station and attach them to the opposite train that they came in with.

Returning via the RRL

I was about to head back to Melbourne. The weather was turning crap and there weren't too many good photo locations (that weren't smothered with enthusiasts) along the return route. I then realised I hadn't gotten a proper shot of the trains side-by-side, so I stuck around (a book helped) and decided on Little River to get the shot I'd actually spent the day for.

Of course, I chose the end of the 'parallel run' area and the trains weren't going to actually be side-by-side at this point. They did get very close... R761 was ahead on the approach and slowed right down to allow D3693 to catch up, but then bolted ahead a little too early and made its way back to Melbourne first.

As D3693 approached the platform, the level crossing activated. It seems to have then faulted, as the lights were flashing but the gates didn't come down. Cars built up and then started crossing. A V/Locity crawled its way from the other direction on caution as the light must've also been red from the other side. After a 20 minute wait, the gates came down properly and the steamer was given a proceed back to Melbourne.

I returned to Melbourne also. Really great day out!

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28Oct/162

Latest 386 Hardware Acquisition

Whilst browsing the usual Vintage Computing column on eBay, I came across a naked computer. The seller described it as a functional 386 with RAM, CPU and all cards/cables; but no disk drives. No real issue there as I had the missing components at home.

Upon further inspection, a few of the cards caught my eye. They were all 8-bit ISA and had huge IDC headers on them. One had 4-in-a-row internally and another had one on the rear plate. These seemed to be I/O controllers, and so I endeavoured to win the auction.

Once everything arrived, I asked a few more questions and was told that this rig was initially in a corroded standard PC case (of the time) and had a large quantity of ribbon cables hanging out the back. This makes perfect sense as each of those headers would fit a 50-pin ribbon cable, and four of those hanging out the back would take up a lot of space. I was then told that the machine was used at the Siding Spring Observatory. Who would've thought that a random 386 would have so much history!? No wonder they needed so much I/O!

I googled for images of internal computer systems at the observatory, but couldn't find any pictures of anything resembling this machine. Here's some links: The 2.3m Advanced Technologies Telescope at Siding Spring Observatory, Anglo-Australian Telescope control room, 40 Years of the Australian Astronomical
Observatory and The Anglo-Australian Telescope and Siding Spring Observatory.

The Loot

386 Motherboard
ELTECH 386 ELT-386B Cyrix 387 FastMath Coprocessor	Very OEM-looking board, but turns out to be a popular brand back in the late 80s. This is nearly the board, but it seems like there is very little information. There are some brochures on the machines! It gives you a good idea as to what the case used to look like. 8 SIPP modules installed. These have pins, instead of an edge-connector, connecting them to the motherboard. Very difficult and fragile to deal with! The EEPROM was oncovered to start with and the sparkly internal chip was visible. I'd not exposed it to direct sunlight, but I was worried for it's 1s and 0s! The battery was also in an awful state. This was removed and cleaned up post-haste.

16-bit Controller Card
PRIME 3B MKII	Nothing special about this card...just your standard ISA 16-bit controller with all cables and ports provided for.

16-bit VGA Card
ZPVGA REV:B ZTECH Electronic Corp Licensed by WDC	Really nice 16-bit VGA card. Seems to be a clone (or produced under license) of WDC.

Axiom Tech AX5210 A/D Interface Card
8-bit ISA bus with 50-pin IDC male port. 16 analog/digital inputs. 8 Digital-only inputs. 8 digital-only outputs.	This thing looks awesome. At first I thought I'd have trouble with connectors, but it uses a standard SCSI 50-pin IDC connector! There's a lot of documentation and (thankfully) the source code online too! Acceed.net product information page Acceed.de product information page Driver pack with sample code!

8-bit ISA I/O Card
All cabling internal. Small slot under backplane to allow ribbon cables through? 4 50-pin IDC headers.	This thing is huge. After investigating the ICs I can see that there are 8 74LS244Ns that run to the 50-pin IDC ports. Therefore I'm guessing this is a 64-bit I/O card. Programmable as well. Maybe similar to this. Zero documentation online, but I did find another going on eBay for over AUD$100!?

8-bit ISA I/O Card
DECISION-COMPUTER DECISION 9012-1 2 PORT 422/485 I/O CARD Startech Semiconductor Corp (on chips) PLC 37-pin Female Socket	Not much online for this one either. Seems to be a 2-port RS422/485 serial card? Not overly interesting as I have nothing else for it to talk to! Here's a datasheet of the major ICs on board (ST16C550CP). Actually, Here's the link to the exact card.

AT Power Supply
TERVAN PTY LTD "INSTALLED 29 JULY 2004" "FAN REPLACE 25 JAN 2011"	This power supply has, relatively recently, been maintained? Does that mean that this machine was still operational at the Observatory right up until (or past!) 2011? Amazing usage of the rule don't-fix-what-ain't-broken!

Quick POST Test

Yes, the age-old Power-On-Self-Test-Test. Just like the ATM Machine. Not all of us know English. Anyway... removed the battery, cleaned the area of residue and thankfully there was no corrosion! The motherboard was inspected. The power supply was too.

All received a brief clean and then the machine was assembled on the workbench with the VGA card installed.

Ta-da!

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27Oct/165

Sony PCG-C1VS/BW PictureBook

I've always loved this form-factor. Sony did a really great job early on with their Vaio C1 Series subnotebooks. Known as the 'PictureBook' (Product Brochure), it's a pocket-sized letter-box bundle of fun. This is one of the first, from Japan, with the a Transmeta Crusoe 600mhz. You may not have heard of Transmeta... they were the first company in a long time to try and beat Intel at their game and built 'low power' but performing CPUs for the 'mobile' (laptop or hand-held touch-screen [this OQO]) device market.

It came installed with Japanese Windows 2000. Not much fun and took forever to boot, so I attempted to get Windows ME on to it. Yes... Windows ME... there's even a sticker on the machine stating that it is designed for it! I didn't have an external drive for it, so I couldn't boot off anything but the internal HDD. It can't boot off USB, so you'd need one of the proprietary Sony external PCMCIA CD-ROM drives if you wanted to go down that route.

Instead, I grabbed a larger 2.5" IDE disk that I had lying around and created a bootable partition on it. This wasn't without its own complications! I then dumped the WinME CD onto the disk into its own folder before putting the drive into the Vaio.

Swapping out the HDD

Flip the beast over and take out all of the screws with an arrow pointing to them.

Now take the battery out and pop off the two dark-purple caps. These are only clipped on, but require quite a bit of force. Edge your way around the circumference, prying them off around 3mm at a time.

Once off, flip the laptop back up to its normal orientation and take out the screw top-left on the hinge.

Now pry the keyboard up. Be careful once it is free as there are two ribbon cables that need to be undone before the keyboard comes completely away.

All of these ribbon cables are held into the motherboard by a socket that has a removable plastic 'chock'. Grab a small flathead jewelers screwdriver and pry the chock up on both sides. Once it has shifted around 2-3mm then the cable can slide out. To put it back, lift the chock, slide the cable in and then firmly seat the chock once more.

From here, there are 3 visible screws and one hidden. The hidden one is under the barcode sticker on the middle-right. Towards the right-hand side of it. Unfortunately, if you haven't already guessed, this does void your warranty! With this all undone, you should now be able to lift this part of the case to reveal the motherboard.

Finally, to remove the HDD, lift the ribbon that is strapped across it and undo the 4 screws that hold the HDD caddy in place. Carefully pry out the IDE cable and then lift out the whole HDD and caddy.

Windows Millenium

After slapping the new HDD in, I ran WinME Setup. Everything went smoothly until it booted into the desktop.

The resolution, instead of scaling to fit onto the screen, stretched to only showed me the center of the total view. No real issues here... scouring the internet for ATI Rage Mobility M1 drivers for Millenium provided me with very little. Whilst testing drivers, I also managed to blue-screen the thing; although not a real error, as it was my fault for removing a USB key prematurely. Actually, it wasn't even a real blue-screen... just a forceful way of Windows trying to convince users to cleanly unmount disks.

At this point I realised that I probably didn't want to run WinME as the default anyway... so chose to install WinXP.

Installing Windows XP

Use a 'non-ramdrive' boot disk from AllBootDisks for Win98SE. Parition, format and sys your disk and then copy the contents of the floppy to a folder called TOOLS on C:. Also grab the relevant XP install media and then copy the whole lot into a folder called WINXPCD on the disk. Once you've transplanted the HDD back to the VAIO, boot it up, CD to TOOLS and run SMARTDRV. If it complains that HIMEM.SYS is missing, then add a CONFIG.SYS to the root of C:\ with the single line DEVICE=C:\TOOLS\HIMEM.SYS and reboot.

Once SMARTDRV is running, switch into the C:\WINXPCD\ directory and run I386\WINNT.EXE. You'd be forgiven for thinking SETUP.EXE was the correct file; this isn't the case! The installation may ask you where the files are... if it does, usually the answer it provides is the correct one. Otherwise just give it C:\WINXPCD.

Big note: If you get any errors during install (specifically regarding "setupORG.exe" or "presetup.cmd") then you're using a crappy copy of XP and need to find a legitimate MSDN ISO. You cannot, without edits that I haven't bothered to investigate, install the ISO you are using from your HDD.

You can then get all the WinXP drivers for this machine from the Sony Japan site here. If you can't handle the Japanese, then this third-party driver site might also help.

RAM Upgrade?

This japanese blog post seems to indicate that the user bought a picturebook with a 64mb upgrade in it and, after inserting a 128mb upgrade, the machine still displayed 192mb. This aligns with the specifications that say 192mb is the max anyway. Of course, Sony has used a proprietary SIMM slot and connector, so it'll be near-impossible to find anything. They seem rare on Yahoo Auctions... but I'll keep an eye out.

Further research brought me to this page on the PCG-C1XG which lists the memory modules available. Turns out there is a Sony official product for the 64mb upgrade and one is on its way to me from Japan!

*NIX?

Back at the Linux User Group at ANU in Canberra, the main developer of SAMBA (Hi Tridge!) had a PictureBook and pretty much wrote all the required drivers to get the machine up and running. Back then, the RAM this machine had would've sufficed with the relevant Linux distribution. I would love to know what version that was just to match all the generations up correctly.

Meanwhile, here's a random PDF full of information on customising the OS installation. They use System Commander for the boot menu and Vine Linux for the distribution. They do expect an external CD-ROM drive though!

I might try and find an external drive for this beast... otherwise I can slap the HDD back in a virtual machine and try and start the installation that way. Maybe a netboot first, transfer to real machine with PCMCIA network card and go from there?

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25Oct/160

Creating a bootable DOS HDD without a boot device

I've come across this problem twice now. Both times it has been with older 'subnotebooks' which have no internal removable media and don't have the ability to boot from external drives. You also may just not have the ability to create a bootable floppy disk.

The problem also occurs when you have a harddisk, a USB to IDE converter and you want to make a bootable DOS partition on it. This can be done with USB keys, but HDDs, when attached to the USB bus, appear differently and most tools wont want to work with larger drives.

Using a virtual solution

Most emulators allow 'direct disk' access to physical drives attached to your PC. This can be a godsend, or can be seriously dangerous! I've tried a few now, and I'm a total fan of VMWare. Both DOSBOX and Virtual Box failed me.

DOSBOX got very close... I created a partition using diskpart in Windows 10 and then mounted the new drive as c in DOSBOX. I then mounted a DOS 6.22 disk image and tried to run the fdisk/sys/format commands, which all reported Incorrect DOS version. Booting DOSBOX with the floppy image resulted in not being able to access the HDD at all.

Virtual Box, with a lot of trickery, allowed direct physical access to the HDD. Unfortunately, the format and fdisk commands failed miserably with out of space (or other random) errors.

Preparing your disk with VMWare

Find a suitable version of VMWare Workstation and create a new virtual machine. It doesn't need to be high spec; give it 64mb RAM and no storage. Attach a floppy image (grab one from AllBootDisks). Next, go to Disk Management in Windows and work out your drive number. You can see below that I want drive number 3.

Once you've got this, you can configure a new storage device in your new virtual machine.

If you chose Entire Disk then you'll be able to do the whole lot, regardless of the drive state, with VMWare. Otherwise, choosing Individual Partition will mean that you'll need to partition the drive somewhere else first.

Once you're booted, you should be at a DOS prompt with all the tools you'll need. Run fdisk first and create your partitions. Make sure you set one to active!

Reboot the machine at this point, just to make sure all settings stick. Once back in, run fdisk /mbr for good measure. This will properly re-create the MS-DOS Master Boot Record that'll allow your BIOS to find your active boot partition.

Now that you've got a valid partition, run a format c:/s to format C as FAT and transfer system files to make it entirely bootable. Give the partition a label when it asks.

Copy Windows Setup Files

Grab a copy of your favourite windows from WinWorld. This particular laptop was 'built for Millenium'... hah... so I retrieved that ISO. I loved the screenshots!

The best thing to do at this point (and the whole reason why we're here) is to copy over an entire Windows setup folder to the disk. This means that setup will be really quick and, down the track, you'll always have setup files handy. Remember how many times WFW311 used to ask for the network disk? Even if you were just changing IP configuration?

Note that the copying of the Windows Setup folder can be done outside of an emulator. The proviso here is that your host can read the format of the newly partitioned drive. Once copied, cleanly unmount the disk and get it back into the target machine.

If you get to a DOS Prompt, then you should only have to change to the windows setup folder and then run setup.exe.

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24Oct/160

Melbourne – 3rd Quarter 2016

You'd probably not think it... but this site was actually created to talk about (big and small) trains. I've been pretty distracted lately by vintage computers and other such electronic fun. Just for something different, I thought I'd throw in an update on the latest happenings around Melbourne.

Regional Rail Link

This line, from Sunshine to Manor Loop, has been completed for ages and is functioning well. The first station on the 'new part' from Deer Park is Tarneit, followed by Wyndham Vale. There is then a loop in the middle of the bi-directional tracks for peak-hour services to return. Every afternoon a push-pull set utilises this.

From Tarneit Station, you get a great view of the Melbourne skyline as you look east-ish back to the city. There's also a nice long curve, on which an approaching service would be very photogenic in the right lighting conditions. Unfortunately, Melbourne's weather is shit.

Every so often a 'hospital' train runs from Tottenham to Geelong. These trains consist of ill rollingstock requiring servicing in Geelong and a BG engine (normally a G or an XR) hauls the lot west. This movement has been known to traverse the RRL and Tarneit would provide a great vantage point to get a shot of it.

I saw the right locomotives appear on the radar in Tottenham and got in position at Tarneit. Unfortunately the train took the old way through Brooklyn and Werribee. I was still fortunate enough to get the Down Warrnambool service.

I was actually on the station platform when I saw that diesel approaching... hence missed the skyline in the proper shot!

Moonee Ponds Creek Viaduct

This amazing piece of architecture was built for the opening of the Albion Jacana Railway Line in 1929. The State Library Victoria has some awesome photographs of the construction. I was out there one early morning in August to see Steamrail traverse the bridge.

The XPT showed up first. V/Line's SG set then came through into Melbourne.

QR were hot in pursuit with a Melbourne-bound freighter.

And then Steamrail's A2-986 came through on it's first long run since it was returned to service.

The AK cars were southbound... so I hung around for them as an added bonus.

Meanwhile, back in South Yarra

For the first time in a while, a very clean and shiny XR lead the Long Island train south. Seems they were doing work on it as the side-panel on the loco was wide open and you could see the engine working hard as it went past.

I then tried some new angles from random legal spots trackside.

That last one is a new favourite! There's a sound-proofing wall near my place that allows the puppies to play in a park without train noise... Fortunately you can get behind it, still on public land, and grab a really nice angle. Now we just need daylight savings to stretch a little later.

Meanwhile the mud-holes are just getting worse!

R707 to Seymour

R707 Operations took their steamer from Southern Cross to Seymour and I tried to get it at Kensington. If it wasn't the sunlight that was going to ruin the shot then it was to be a bloody spark.

Steamrail's Rail and Sail Tour

This was to go via Werribee, so I thought I'd check out the tracks down that way as it's been a while. I started at Lara in the morning, and then, as that I'd never photographed from it, chose Williams Landing for the return trip.

A G-class then bolted east with 4 locomotives in tow. This little blighter wasn't on the radar and snuck through... would've been a great shot! On the return journey, the freighters first put on a show... but then the weather turned to poop.

Footscray Vantage Points

Thanks to the Regional Rail Link mentioned above, there were a number of buildings demolished when they added the extra two tracks through. As long as you are careful (seriously! watch out for syringes!) then you can get a good shot from Short Street, just off Albert Street. 42202 just happened to be on its way through with an SCT shuttle. I've never heard such a loud flat-spot on a loco!

What's next?

Steamrail Victoria are parallel-running two steamers to Geelong next weekend. This should actually be really cool... as long as the drivers lock-step and don't try to race. They'll then parallel run back... via the RRL! Too bad they'll be facing in the wrong direction. Either way, should be a good day out.

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20Oct/160

Compaq Deskpro 386s/20n: Onboard VGA

This machine only has two ISA slots available, so options are immediately limited for anyone who wants sound, network and upgraded video! Currently the machine is running (what I believe) is a better spec VGA card and a Crystal sound card. I wanted to also try a network card, so I have endeavoured to get the onboard VGA working.

Rear plug - blocked pin?

The port is there, but back in the day they blocked pins so that you could only really plug in Compaq monitors. I don't know if this was to make sure that you gave money to Compaq, or if they were worried about monitor compatibility.

Either way, I now had to either destroy a VGA cable or build an adapter... I chose the latter.

The adapter was simple... just don't connect the blocked-out ground pin. It didn't work... well, it did, the adapter worked fine on the add-on VGA card. Once plugged in to the on-board VGA, with dipswitches set and the add-on removed the machine just didn't boot. No beeps, nothing.

Motherboard dipswitches

These are pretty simple. Smush in the top side to set them to 'ON', the bottom side for 'OFF'.

As per the instructions.

I love it that it says 286N. Silly Compaq... re-using old cases for new hardware.

No dice

Maybe that 'X' above the port was put there when the onboard video failed decades ago? I've no idea when, but it doesn't work. Hence why the owner bought an add-on video card? What are my options here?

I straightened the pins that you see bent above, but that didn't work... I was a little sad... I wanted two ISA cards in there. This board could nearly be considered a total loss if it was partially-working. I have no real way of determining what else could be malfunctioning.

Maybe I should 'reflow' the board as described in the process here?

Reflowing, what could go wrong?

I killed it. I totally killed the motherboard. DO NOT REFLOW OLD ELECTRONICS. But this is what it looks like anyway... Bake away, pretty motherboard.

The idea is that, by heating the board to 200 degrees celsius, you'll re-connect all the solder joints that have aged badly. I hardly put the thing in the oven for a few minutes (less than 5) but it stopped working afterwards. Turns out that the board uses tiny solder joints to connect the top layer to the bottom layer and most of these succumbed to gravity. None of my efforts to re-connect these solder connections worked.

I managed to re-seat that PLCC socket and replaced all the electrolytic caps that were bulging... gah. I assume I've done massive internal damage to the ICs though. Meanwhile, the little motherboard top-layer to bottom-layer solder joints are all stuffed.

Anything above or below that looks like a solder ball sitting on top of a hole in the board shouldn't be there. Above is the underside of the board and the solder has dropped out of the hole and is hanging in a nice sphere. If you look closely, and I apologise for the focus, you'll see 3 spheres, just below the right-hand-side of the edge connector. They shouldn't be there.

Below, if you see holes resembling black-heads then you'll realise that there should actually be a nice flush bit of solder there!

I attempted to re-solder with my soldering iron... but a lot of the joints just wouldn't accept the solder... I'll store this board, I'm not accepting defeat just yet... but I'll need a solder-sucker and a higher quality iron to get it going again. If the ICs are dead. Meanwhile, another motherboard is on its way.

Maybe I should put it back in, upside down?

Defeated...

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18Oct/160

Take The A-Train (MSX) – Don’t trust the save option!

Here I was, building my little railway... saving fastidiously along the way to make sure I had a restore point to return to. There is only room for one 'save' in the game (stored in SRAM), and so I knew that each time I saved I overwrote the previous save.

Upon closing and restarting the emulator, I tried to load my save-game and got the following:

Hah... the map has loaded with no tracks... the trains then try to move and just crash! I wonder if this is a Japanese Cartridge thing?

Does saving work on fMSX?

I downloaded fMSX and tried the same thing. Firstly, it was not as easy to get the game running! Make sure you set the cartridge type to: ASCII 16kB Mapper. Once running, I ran into the same issue:

That last shot is even better... it happened after I adjusted further settings... proves that this is a save/load from SRAM issue... maybe endian or somesuch?

Your best bet?

Use the save state functionality built-in to each of the emulators. I successfully saved and loaded an STA file into BlueMSX. They'll also give you an unlimited number of saves, rather than just overwriting the same save in SRAM each time.

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13Oct/162

Compaq Deskpro 386s/20n: More RAM

This has been a challenge. The user manual only really indicates the spare-part numbers for modules, but searching for those proved difficult. Therefore I went in for the lucky dip and purchased whatever I could find on eBay.

First was a cheap batch of unknown SIMMs. They all turned out not to work. I then purchased 2x4mb EDO SIMMs specifically by Compaq, but they didn't work either. There's a few FPM SIMMs below that should work... maybe they've been damaged by static or are of the wrong spec. Seems like I need compaq-certified FPM and hopefully I've now ordered the right parts.

Here's what I've got, what worked and what didn't. I've used the DRAM info page at retro hardware to try and determine the module information.

Update: There's a link here at efetcher that indicates I need parity RAM.

Module details	Chip details	Status
Original 2mb SIMM (256kbit x 4) x 16 = 1mbit x 16 = 8MB x 2 = 2mbyte	HY4424 COMP#118689-001 KM44C256BJ-8 (x16) KM41C256J-8 (x8)	Works - 2mb

Compaq 2x4mb EDO SIMMs	Compaq 185173-002 - EDO - 4MB Fujitsu 814405C - 60 9269 F98 (8 chips)	Does not work

Could be SMART CQ SM5321000W-7 1mbit x 16 = 2mbyte x 2 chips = 4MB	HY5118160 JC - 70 9545A KOREA (2 chips)	Does not work

4MB DRAM	Singapore TM248GBK32U-60 9706 TM5418169DX (4 chips)	Does not work

4M bit dynamic RAM organized 1,048,576 x 4-bit 4mbit x 8 chips = 8mbit (1MB) x 4 chips = 4MB Maybe EDO?	HY514400A J - 70 9512B KOREA (8 chips)	Does not work

IC 4M X 4 FAST PAGE DRAM Another 4MB FPM?	VG2617400EJ ABORL1 - 6 (8 chips)	Does not work

4M bit dynamic RAM organized 1,048,576 x 4-bit Officially EDO. 16 chips = 8mb.	SEIWA - Made in Japan HY514404A LJ - 60 9461C KOREA (16 chips)	Does not work

4M bit dynamic RAM organized 1,048,576 x 4-bit Officially EDO. 16 chips = 8mb.	4mb 72-pinn PARITY SIMMs	WORKS! - 8mb