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@Retrochallenge – Heath Robinson
CMOS Battery Pack
I switched on the BBC Master this morning and was again greeted by the ‘This is not a language’ error. I’d pretty much fully expected it given that I’d already assumed the CMOS battery pack was dead.
I opened the old girl up and located the pack. Fortunately although it had leaked it was positioned such that it hadn’t caused any damage.
I don’t know whether it’s the original pack, it’s certainly pretty old, you don’t see Vidor (‘They last about a month longer’) batteries any more. In fact you don’t see much that’s made in Britain any more but that’s another story.
There are several easily found guides to building a new pack. I found this one to be very good. It explains clearly that a resistor and diode are required within the assembly to inhibit the charging circuit intended for the Lithium cells that were originally fitted, also suggesting that my pack was indeed a replacement.
Leaking Batteries
I’m learning quite quickly that there’s an impressive and very active community attached to the BBC and other Acorn models.
My wallet is also slightly concerned by the amount of mods that are available, I fear my Master will soon be sporting some interesting additions.
Hopefully aforementioned community won’t see the rather Heath Robinson replacement battery pack that I hacked together. Short of parts to build a proper one and aware of the limited time left in this year’s Winter Warmup I’m afraid I resorted to copious amounts of insulating tape and reuse of the original resistor/diode assembly.
Quality Engineering
I include an image here for entertainment purposes only. It works and will see me through the next few days until I can put something a little more professional together.
Of course all this diversionary stuff means I haven’t added any code to Yahtzee and I’m wondering whether subconsciously that’s kind of intentional.
Thanks also to other Retrochallenge participant Andrew Hazelden for pointing out that the formatting in the code I’d previously listed had gone awry. This in turn led me to discover that there’s a WordPress shortcode you can wrap around code to preserve its formatting.
The original post has been duly amended.
@Retrochallenge – Getting Started
I have one definite project that I want to complete this year, building a multi-boot bridge machine. This is more of an enabler than a full on retro project and will likely prove far from taxing, hopefully taking only a few hours.
Once achieved however it will allow me to seriously de-clutter my workspace and this in turn will hopefully allow me to get on with some other retro goodness without the continual hindrance of being surrounded in junk.
Choice Of Cases
Due to the ubiquitous nature of MS-DOS and the various subsequent flavours of Windows most of the retro computers in my collection rely on connecting to Wintel machines to facilitate file transfers. Some of the software provided is very specific about which version of DOS/Windows it will play ball with. I therefore have a collection of machines running early versions of DOS through to Windows XP. My aim is to narrow this down to one machine.
Helpfully Microsoft still provide minimum specifications for Windows For Workgroups and XP.
Windows For Workgroups:-
- 80286 microprocessor or better for version 3.1
- 80386sx microprocessor or better for version 3.11
- 2048 kilobytes (K) total memory for version 3.1
- 3 megabytes (MB) total memory for version 3.1 (2 MB with no network installed)
- 3 megabytes (MB) total memory for version 3.11 (4 MB is recommended)
- 6.2 MB of hard drive space (14.5 MB recommended)
Windows XP:-
- Pentium 233-megahertz (MHz) processor or faster (300 MHz is recommended)
- At least 64 megabytes (MB) of RAM (128 MB is recommended)
- At least 1.5 gigabytes (GB) of available space on the hard disk
- CD-ROM or DVD-ROM drive
- Keyboard and a Microsoft Mouse or some other compatible pointing device
- Video adapter and monitor with Super VGA (800 x 600)or higher resolution
Choosing A Motherboard
I delved in to my collection of motherboards and cases and decided to pair an Abit BH6 motherboard with a 300 MHz Pentium 2 ripped from a dead Dell Dimension. The BH6 has a good combination of ISA and PCI slots, USB, standard serial and parallel ports. It’s had an interesting few years, some of them spent hanging on the wall as decoration (regularly vacuumed in a non sympathetic manner) and the last 2 or 3 in a pile of other MBs in a damp, non heated shed. I was therefore a little sceptical as to whether it would still work.
I also found an Nvidia TNT 2 graphics card, two 128MB sticks of PC100 RAM, a 3.5″ FDD and a CD-ROM drive. I assembled all of the components into a suitable case and was somewhat surprised when greeted by a successful POST.
Compact Flash Cards
I decided in advance that the easiest way to boot into various OS’s would be to use Compact Flash cards. I have a number of them lying around in various sizes from 32MB up to 16GB and have had great success with them in the past.
I had therefore ordered an IDE to CF adapter with a back plate fitting so that the card could be swapped out easily. In retrospect a 5.25 Bay model would have been even more convenient so I may yet get one of those.
CF Adapter
Once fitted and hooked up with a suitable cable I set about installing Windows for Workgroups, Windows 95 and 98 onto separate cards. The installations went pretty smoothly, I put DOS 6.22 and WFW on a 32 MB card, Windows 95 on a 1 GB card and 98SE on a 4 GB card. One other useful aspect of this method is that the cards can be easily removed and inserted into a card reader on another machine allowing easy transfer of files.
Installing Windows For Workgroups
Having discovered some old floppy disks whilst rooting around for components for this machine it wasn’t long before it was called in to action. I installed a 5.25″ FDD into a spare bay and inserted the Windows 95 CF card. Once booted into Windows 95 I set about attempting to recover some old files as detailed here.
The build has therefore been successful, I’ll also do an XP installation and then I’ll be able to simply swap cards and boot into whichever OS I need. I shall also add an internal CF adapter with a 4 GB CF card onto which I will install all of the retro software that I need so that it’s always available to each OS.
Pentium II & Heatsink
The machine is reasonably quiet as the Pentium is passively cooled although the graphics card has a small fan, I may therefore root around for a fan-less model.
A sound card would be nice but not essential and I may see if I can hook up the two Voodoo 2 3D cards that I used to run in SLI mode.
@Retrochallenge – Recovering The Past
Some of you will no doubt be familiar with last year’s story surrounding Jordan Mechner’s discovery and recovery of the Prince of Persia source code, you can read about it on Mechner’s blog here.
I suspect many of us have on occasion stumbled upon old floppy disks stored away in the back of cupboards or in our lofts. Over the years I have found several stashes of both the 3.5″ and 5.25″ variety. It certainly seems to be pot luck as to whether they are still viable and whether any recoverable data remains, although I have noticed that certain brands seem more resilient, 3M, Dysan, Verbatim for example.
In the process of searching for components for my bridge machine I stumbled across another such stash in my loft. I found my original Amiga game disks, titles such as Defender of the Crown, Monkey Island, Frontier and so on, some Amiga joysticks, a Philips CM 8833 monitor and most interestingly for me a box of 5.25″ disks.
28 Year Old Floppy Disks
On closer inspection of the box I found two disks that I had used back in 1985 for my computer studies class at school. What chance I wondered if any data could be recovered?
The computers that we used at school at the time were BBC Model B’s. I don’t currently have any BBC machines in my collection although I now feel a strong urge to acquire one along with the Microvitec Cub monitors that were ubiquitous at the time. I therefore had a look around to see if there was any software that might allow me to read the disks in a PC.
I quickly found the superb OmniDisk by Jason Watton and nervously inserted the first disk. After working my way through all the options it became clear there was nothing to be found on the disk. Of course there may not have been anything on the disk in the first place so undeterred I turned to the second disk, barely legible on the label, mine and Urbancamo’s form group – 5C4.
Recovering Files With OmniDisk
Immediately it became obvious there was some data there. I ran through the various options in OmniDisk (did I mention how superb it is) and eventually managed to extract an image from the disk and from this I was able to pull out the individual files.
Loading these into a text editor revealed that they were BBC BASIC programs, namely my game ‘Yahtzee!’ and Urbancamo’s ‘Airman’. Not exactly Prince of Persia but nevertheless pretty exciting on a personal level to recover such data from a disk that is the best part of 30 years old and has spent most of its life suffering the extreme temperatures of life in the loft.
The files are stored in tokenised binary format which results in a lot of garbage when viewing them in a standard text editor. I had a hunt around and found the BAS2TXT DOS program here which converts the files into readable text.
BAS2TXT Conversion
It worked very well although I still had to jump in and make a few manual corrections, but then that was ever the case when it came to my laughable attempts at coding. That’s why Urbancamo did the coding and I did the pretty things.
I’ve also recovered Urbancamo’s ‘Airman’ program and sent it to him, I think he may be incorporating it into his Retrochallenge which would be cool. Perhaps if he can finally finish that, he could move on to his PhD, snork.
Anyway, the next challenge was to see if I could run the code. Nostromo BBS user Stuart Johns pointed me in the direction of BeebEm, and I found a Mac version courtesy of Jon Welch.
I fired it up on my Mac Mini, copied my newly cleaned up code and pasted it straight into the emulator window, typed RUN and slap my thighs it worked!
Yahztee Running On BeebEm
There on the screen my hopelessly inept attempts at coding in full view for the first time in 28 years. Yahtzee!
There was even sound.
Subsequent attempts to access the original floppy disk have failed, it seems this really was last chance saloon stuff. Of course in the grand scheme of things it’s largely irrelevant, but on a personal level recovering those files has been a real ride and has brought back some fond memories.
Roll The Dice
If I can find a Beeb at a sensible price I think it may well be my next purchase.
Retrochallenge Winter Warmup 2013
Retrochallenge Winter Warmup 2012 Open For Entries
Good friend Urbancamo has contacted me to let me know that the 2013 Retrochallenge Winter Warmup is now accepting entries from those who wish to participate. Running through January 2013 it’s a great excuse for dusting down your retro gear and finally completing that project you’ve been putting off.
Thinking cap on, time to decide what I shall do this time around…
Hunting Huskies
Tough, rugged, angular, ugly… that’s enough about me, my Husky Hunter 2 has arrived. I’ve lusted after some military computing hardware ever since I first saw the GRiDCase controlled remote sentinels in Aliens SE. I’ve yet to come across an affordable GRiDCase but was pleased to catch this Husky instead.
Husky Hunter 2
Running the CP/M 2.2 compatible Demos this British made machine is physically designed to handle some serious abuse, an Epson PX-8 pimped by Lucius Fox if you like. Built by Husky Computers of Coventry and introduced in 1984 the unit runs an NSC800-4 Z80 compatible CPU and runs on four AA batteries.
Base RAM specification was 128K althoughup to 726k could be added. Ports are limited to one DB 25 RS 232. There’s a circular 4 pin power connector on the back.
Back of Unit
After inserting four AA batteries I was initially unable to start my Hunter so I had a quick peek inside to check that the backup battery hadn’t leaked and fortunately it was fine, there was also a large pack of silica gel in there for moisture protection. On reassembly the unit powered up and a quick bit of research online revealed that the backup battery needs to draw some juice from the AAs before the Hunter will power on.
System Menu
On boot you’re presented with a splash screen and press any key prompt, doing so takes you to the main screen and command prompt. There are eight pre-defined keys selected by pressing the CTL/FN button with numbers one to eight. One and two are the familiar CP/M commands DIR and STAT, three starts BASIC, four allows you change the communication protocols for the RS 232 port. To set the clock select five, six launches a terminal software, seven the Edit command and finally eight allows you to toggle to another set of options including Inp, Save, Type, Ren and Send.
Secret Warning
My Hunter has arrived with a rather fetching ‘Secret’ sticker on the back warning that ‘This Winchester has been used for classified material and is to be treated I.A.W. current regulations in BR 4005‘ so there! Of course any information that may have been held in the RAM disk is long gone, indeed issuing the DIR command would initially crash the Husky every time until I formatted the drive. I’m aware that ‘Winchester’ became synonymous with any make of fixed disk but I’ve not seen it used to describe a RAM disk before.
There’s a very useful unofficial Husky Hunter 2 wiki here for which I am unable to identify the author but whoever you are I am very grateful for your efforts. From there I downloaded the HCOM file transfer utility and followed the excellent instructions provided for installing it on the Hunter. I ran the DOS client on my Windows XP box and the two machines were soon talking to each other via null modem.
Connecting With HCOM
I transferred over a copy of the CP/M version of Level 9′s Snowball which ran well, albeit with the need to horizontally scroll backwards and forwards to read the text.
I also took the opportunity to try the built in terminal software to connect to my BBS Nostromo which allows local connections via null modem and this worked without issue.
The built in BASIC interpreter is apparently quite powerful so I may have a dabble with that, meanwhile I’ve added some more images and links to resources below. Oh and I’ve just realised my model has a backlight, cool, but not very bright.
Battery Compartment & RS 232 Port
Left Side, Tripod/Strap Socket
Serial Number
Husky Hunter 2
Keypad
Nostromo BBS – FTP, Telnet and Dial Up
After several months as a dial-up only BBS I recently opened up access to Nostromo via telnet. Still running reliably from a SanDisk CompactFlash card installed within a Wyse Terminal the discrete unit sits quietly in the corner of my office happily doing its own thing, the only reminder of its existence the occasional screech of the modem responding to a user connecting via dial-up.
Nostromo runs on the simply superb Synchronet BBS software created by Rob Swindell. Not only is Synchronet a fantastic piece of software but the available documentation makes using it child’s play, even for an eejit like me. Rob even helpfully provides a free easy-to-use dynamic hostname service which I have taken advantage of. You can therefore now reach Nostromo via telnet at nostromo.synchro.net.
Wyse Winterm
Enabling telnet access has unsurprisingly led to more visitors both welcome and unwelcome. It’s been a pleasure to welcome some new users and somewhat less welcome though admittedly interesting to witness various attempts by spammers to relay mail through the mail server. None of these attempts have been successful and nor will the be, but they are persistent and I may be naive but I am amazed at the speed with which they descended upon the newly Internet facing box.
It is now also possible to FTP into the file area of Nostromo. You can do so, if your browser supports it by FTP’ing to nostromo.synchro.net. I have been and will continue to add an eclectic mix of files that I’ve found useful over the last couple of years whilst tinkering with retro gear. Thus far I have concentrated on stuff related to the Epson PX-8 and whenever a few spare minutes present themselves I shall continue to add files.
Epson PX-8 With The CX-21
A recent Google search for Epson PX-8 software led me to this page, an archive of a 1997 post to the comp.os.cpm usenet group. Without much hope (assuming the contact details to be out of date) I fired off an e-mail to its referenced author, Bill Esposito, to enquire if he was still in possession of the files from the PX8 dedicated BBS, PX Dock.
Much to my surprise and delight Bill responded quickly and generously sent me an archive of all the files he had. I shall therefore be sorting through these and adding them to Nostromo in due course.
Anyway, if like me you get a strange buzz out of the thought of being remotely served files from a CompactFlash card you’re more than welcome to FTP in to Nostromo.
@Retrochallenge 2012 – Under Construction
An illness in the family has rather curtailed my retro activities this year. Any grand projects are unlikely to reach fruition, however I’m still tinkering with odds and sods.
I finally got around to Telnet enabling my Nostromo BBS, which was previously dial-up only. Trouble is I may now therefore actually get some visitors and that in turns means I ought to add some content.
I hadn’t realised, but my Broadband supplier at work, Demon, actually furnishes me with a static IP address so the process was very simple. I had previously assumed it was a dynamically allocated address. I also still have my original ‘tenner a month’ dial-up account with Demon, purely to retain the associated e-mail address. Next year will mark twenty years since I first signed up for this account and it occurred to me it would appropriate to create a suitably retro-style website on the included web space.
So you can now visit the hand coded Nostromo BBS Website replete with snazzy background, marquee, page counter and other early 90′s Internet goodies. Twenty years, I can’t believe it!
@retrochallenge 2012 – Recreating The Past
I recently discovered an original brochure for the Epson PX-8 system and accessories. In it is an image of the PX-8, along with the CX-21 acoustic coupler, the PF-10 FDD, and two printers, the P-80 and P-40. I was pretty sure I had at least one of all these items kicking around in my collection of retro gear. It occurred to me it would be fun to try to recreate the aforementioned shot given that almost 30 years had elapsed since it was originally taken.
Epson Printer Advertisement
I delved into my many boxes of gear and pulled out everything I needed. It was then I realised there was one item that didn’t match, what I’d thought was a P-80 is in actual fact a P-80X which varies slightly in appearance. Its plastic has also yellowed much more than the other peripherals and looks particularly bad when seen alongside what was my ‘new in the box’ PX-8. I’m now wondering whether I should perhaps consider a session of Retr0brighting, one of those things I’ve always wanted to do but have never taken the dip.
I’ve always had a thing for portable printers and I’m particularly fond of the P-40 and P-80X. Mine are both in fine working order although I’m unable to hook up the P-40 to my Epson gear as it has a parallel interface as opposed to the P-80X which is serial/RS232.
First Test Shot
The P-40 requires thermal paper rolls, the P-80X can apparently print on either thermal or plain paper, I can vouch for the latter. I’m now wondering whether it would be fun to hook it up to the PX-8 and use it as a kind of Teletype with all output going to the printer. Anyway I digress. I arranged all the peripherals as laid out in the original picture and took a quick test shot with which I’m reasonably pleased.
Original Shot
Thus far then not a great deal of challenge on the actual retro front. Time to think of something fiendishly difficult to fail at. That beginner’s guide to CP/M assembly in the above shot has caught my eye, I believe it came with my C128D and I’ve never properly looked at it.
@retrochallenge 2012 – Acoustic Coupling
Since contracting this retro computing bug, after prolonged exposure to Urbancamo, I’ve had a yearning to try to recreate one of my earliest and fondest computing memories. That memory, when recalled, still has the ability to send a little shiver of excitement down my spine. Picture the scene if you will, a musty old office in the maths block of my local upper school. Two spotty teenage boys, myself and the aforementioned Urbancamo. In one dingy corner of the room an ASR 33 Teletype, on the window sill an acoustic coupler and telephone and on a piece of paper, a phone number.
ADC 212 Internals
Thinking we were Matthew Broderick from WarGames we eagerly dialled the number inserted the handset into the coupler and waited excitedly for the Teletype to burst into life. Sure enough the ASR 33 started clanking away and we were in! Not NASA or anything like that you understand, but a nearby college upon which we were able to play a game called Shark Attack! A momentous moment in my computing history and the first and last time that I ever used an acoustic coupler.
Epson CX-21
I have for some time therefore been on the lookout for a working acoustic coupler that I could use to try to recreate some of that experience. After failing to bring back to life a very old Anderson Jacobson ADC 212 model, I was recently lucky enough to sport an Epson CX-21 on Ebay.
It’s in lovely condition, and the original NiCad battery even appears to hold a reasonable charge. It came with an Epson HX-20 in a custom-made case which no doubt accounts for its excellent condition. There was a little blooming on the rubber cups but I cleaned this off with a mild detergent solution and the whole unit looks almost new.
I will of course also need an old telephone with suitable handset and fortunately we still have a couple of 1970′s models at work that thankfully were never thrown out. These old BT models were built to last and the one I chose cleaned up really nicely, in fact it looks so cool I may use it in place of our current home set.
CX-21 Battery
The CX-21 only has two options to select, half or full-duplex and answer or originate mode. It has a standard DB25 port and I have the appropriate cable to hook it up to my PX-8, an Epson 724 cable. This is a modem cable with DB25 at one end and an 8 pin Mini DIN connector at the other. I have two options for terminal software on the PX-8, both previously downloaded, Kermit and Mex. The PX-8 does have a rudimentary terminal application on the built-in ROM but I’ve never had much success with it.
After charging the CX-21 and PX-8 I hooked up the TF-20 FDD and copied over all the software I’d need to the PX-8′s RAM disk so I had the minimal amount of stuff to take home from where I would be calling back to the box running my BBS.
Epson PX-8 With The CX-21
I then spent rather too long trying to get my head around whether I was originating or answering the call, clearly I was originating it and the BBS box was answering but for some unknown reason I’d convinced myself that the coupler would have to ‘answer’ the handshaking attempts of the remote modem.
Nevertheless once sanity had been restored I set the coupler to ‘originate’ mode at full-duplex and dialled the BBS with the telephone. After several attempts the ready light finally illuminated on the coupler and it seemed a connection had been established. However once I’d connected via the terminal software all I received was a screen full of garbage.
I checked all my settings, made sure background noise was minimal and continued to make many more attempts to create a good connection. Eventually I discovered that contrary to my instinct to push the handset more deeply and securely into the coupler, lifting the mouthpiece end slightly out of the cup resulted in a much better connection! Whether the proximity of the transducers was causing some sort of distortion I don’t know but whatever the reason I now had a working connection and was reliably able to re-create it. There are still a few erroneous characters coming through but I can live with that.
I shot a quick video showing the process below, all I need now are a couple of ASR 33′s.
Retrochallenge – Summer 2012
This year’s Retrochallenge will soon be upon us, running for the entire month of July there’s still time to sign up and participate. Head over to the Retrochallenge Website and register your interest.
This year I’m hoping to hook up my recently acquired Epson acoustic coupler to my PX-8 and with the aid of an old telephone dial in to one of the few remaining dial up services out there, and no doubt my own BBS.
Epson PX-8 Brochure
In my previous blog entry I posted some scans of some promotional literature for the PX-8 and it occurred to me that I’m now in possession of the all the hardware shown in the image opposite. I thought therefore it might be interesting to try to recreate the shot.
Other options are to create another instalment for my Silent Running text adventure created with Inform.
