With Nicky away again for the evening I’ve spent most of it in the garage trying to consolidate some of the Beeb kit. Top priority has gone to replacing the 20MB MFM hard disk that was running the Level 3 Econet fileserver software, which was done quite simply once I’d worked out the logistics of it all.

By fiddling with a few A4000s I’d been given, I ended up with a machine capable of running the Level 4 fileserver software in multi-tasking mode. Coupled with a 270MB hard disk and 4MB RAM, I copied it over and started it running. One of the nicer differences from earlier versions is that it doesn’t use a partition, rather it uses the native ADFS filesystem (or whatever filesystem is running, so I guess in theory you could chain a network to another network) – so pretty much with a couple of hours of work I’ve managed to get a mechanism of archiving 5.25″ floppies over to a more reliable disk system, on a box which will read 1.44MB floppies (which was the hardest bit of tonight, finding some of those!).

The A4000 also has an Atomwide NIC in it – the plan being to bridge it over via NFS to the Linux box, which is something that the Level4 fileserver seems to be good at doing (presumably to do with the RiscIX stuff and the Unix workstations).

Next step is to remove the older fileserver at the end of the garage, and get the rack cleared so I can start racking some of this stuff ready for the next BBS to go in there. Hurrah!

Having a large amount of duplicate Acorn 8-bit computer gear in my collection which I’d rather not eBay (given the hassle involved), I’ve decided to take out a stand at Wakefield RISC OS Computer Show on 19th May.

Some of the stuff I’ll be taking along for sale will include things I can’t use or don’t have interest in or time to do stuff with:

• A variety of cheese wedges including teletext adaptors, a couple of 6502 copros, etc.
• BBC Master 128s, BBC Micros, in varying states of configuration.
• Lots of internal boards, SRAM boards, shadow RAM bits, etc.
• Disk drives – there’s a few of these 5.25″ units.
• Domesday LVROM player, which may work or not. It’s got the SCSI bits in tho – never had chance to get it sorted or even test it really.
• Lots of books including Assembler tutorial books, writing BASIC, lots of stuff.
• A pile of original Beeb software and boxed ROMs including instruction manuals.
• The odd printer, CUB monitor, that sort of thing.
• A few Electrons, Plus-blah expansions, and some old Archimedes units.

If there is the interest, I’ll drag along the Econet setup for people to play with a bit. There’s some BBS stuff there and a MUD or two.

Elite is one of the few games I still play (under a BBC Micro emulator, natch). Maulkin just pointed me at an arcade cabinet version. That utterly rocks.

I’ve just wasted my lunch hour dialling into the BBS I set up last night. It’s slow, it’s crufty, it needs some imaginative Hayes commands, but it works – I successfully logged on using Hyperterminal’s pisspoor Viewdata emulation:

You logged on at 05:01:51
It’s now 05:12:02 on the 22/09/06
You have spent 00:10:10 minutes online
Thankyou for calling The Rabbit Run!

(Yes, I know I need to set the real-time clock!)

Hyperterminal has no Viewdata graphics to speak of although curiously it’s capable of doing background and double-height. It also confuses £#_ which I’d sorta expected it to not do since that’s a fundamental of decent Viewdata emulation.

So, having established that the SIP route works and using the out-of-the-box Asterisk UPCM and APCM codecs means that V23 is fine, I think we’re in a state that the proof-of-concept has succeeded and we can probably go on to put more boards online. Hurrah!

This is a memo to myself, because I’ve been reminded this is the third time I’ve been on a futile hunt around the house: You have no DB9 thru-connectors. None. Don’t even bother looking. Just give up now.

Thankyou.

<%image(20060921-nfs.jpg|120|86|)%>It works! It bloody works!

After much sweating and grumbling, I’ve managed to get three stations working on the Econet using JGH’s Y2k-patched level 3 fileserver software. This now means that the network works (ish) without any non-original Beeb bits. Just need to source some more socket boxes, some cables and preferably a fully working MFM or RLL hard disk because this old Technomatic jobbie is on its way out and I can’t keep prodding the actuator with a screwdriver every time I need it to start up.

Honestly, when I did “*I AM SYST” and it worked, I had to do a doubletake. I’m surprised that it’s working at all!

In any case, this is enough for me to continue with my experiments into the Evil Beeb Project. The worst bit is trying to remember the relevant commands to navigate the directory tree since it’s sufficiently different from ADFS to be confusing. It’s also left me wondering exactly how feasible getting BBS software online using NFS will be. Still, it’s an experience (photos here)!

Right, well, I’m going to tidy up the garage worktops a bit now it’s all working, and go through some of the other Beeb stuff to see if I can get station 3 going with a 6502 copro.

Hooray! I’ve managed to get the EPROM programmer working again, so now have a pile more ANFS ROMs for the Econet. I’ve also connected up the last few socket boxes and mounted them on a piece of timber so they’re not hanging around the place tangling up. I’ve now discovered the drop-cables I thought would work won’t (hint: MIDI cables don’t work as Econet cables ‘cos they’re only wired up to pins 2, 3 and 4) so I’ve hit another roadblock. I’ve got enough DIN connectors for 5 cables but that’s not enough to get the network working.

End result: station 1 and station 2 are properly jumpered, although they’re not talking to each other.

In any case, while researching the pinouts I found a lovely quote:

“We showed Bill Gates the Econet network and he said ‘What’s a network?'”
   — Hermann Hauser (Acorn co-founder), 1982

Fantastic 🙂

So what’s next? I’ve not replaced the BBC power supply for the fileserver, and I need some cables before I can wire up the clock box and the terminators.

*sigh*

Having some time tonight and some peace, I decided to go back to building the Econet and getting all that working, able assisted by the guidelines on on the Beebmaster site.

First up was the EPROM programmer (not strictly part of the Econet but important nontheless). After trying to program some more 27128’s I shifted the programmer to the BBC Model B sitting on the workbench (previously it was connected to the Master 512). Lo and behold, the damn thing programmed a couple of ROMs fine, so I’m blaming either Master incompatibility in the UVIPROM software or the Master’s user port. Either way, I now have new ADFS ROMs done and a copy of the Lancaster Assembler. Just means that the main Model B machine is running at PAGE=&2100 but we all have our crosses to bear.

Secondly I thought I might get the Econet actually wired up with the socket boxes. Over on the Beeb list it’s been suggested that cat5 UTP is fine for Econet wiring. While wiring it up, I noticed a bit of a nasty ozone-y smell coming from the fileserver. “Not good,” I thought again (getting deja vu?), and tried to do a ctrl-break. Nothing. A power-cycle didn’t even boot the damn thing up so I think it’s probably the PSU; no worries, I’ve got plenty of spare BBC Model B units around but irritating nontheless. Meantime, I need to get two 9VDC power supplies (wallwarts will do fine) for the network terminators.

So, current status: ROMs blown properly, station 254 out of action, cabling pretty much done (but not tested) and I’ve even freed up a small bit of worksurface to properly hold the 6502 copro for the fileserver itself.

I’d better do some tidying before Nicky and her sister get home otherwise I’ll be in trouble, but I feel quite satisfied I’ve done some more on this!

<%image(20060907-arenalogin.gif|120|83|)%>Way back in the days when I was a nipper hacking around the school’s Econet, I co-wrote (with a chap called Ben Horsley) my first multi-user game which ran on networked BBC Micro machines. Called Arena II it involved a small map, some objects you couldn’t really do much with, and a hell of a lot of file-handling. I was quite surprised to find it mentioned on the BBC Micro mailing list, referring to Jonathan Harston’s MDFS website here, dated 31st October 1990!

Why file-handling? The reason for this was that I hadn’t really worked out the client/server relationship involved (not that Econet facilitated it too much either) and so the whole system was quite clumsy. Filehandling on Econet was great – if someone else had a file open, it locked it so you couldn’t open it from another workstation. This led to lots of fun in a multiuser random-access system such as Arena, where a program would open the ‘current locations’ file, update the user’s position and read the current positions of other users, then close the file; the only way of working out if a file was open was trying it and trapping the error condition.

This now meant that we had error trapping going on everywhere and whenever an error was trapped, the program counter was reset with the function stack pointer (so if you were in a function or procedure, you suddenly weren’t). A chap called Andy Dowson came up with the novel idea of using GOTO (which wasn’t subject to the function stack) to solve that one – thus it was a haphazard melange of GOTO statements and error trapping.

Add to that the repeated hammering of files (30 people all using the system meant that it was pot luck if you got a lock on the file, which caused vast amounts of network traffic) and the network would slow to a crawl.

I’m tempted to rewrite it to use a couple of service ROM images as a server (or perhaps requiring a 6502 coprocessor), with 6502 machine-code based clients, but I’m not sure I can remember all the 6502 stuff nor (I am reliably informed) do I have time. Great days though.

Mmmm, Level 3 Fileserver goodness 🙂

A brief overview of what I’m up to, since a few people have asked:

Way back in the late 80s and early 90s, I was involved in the Viewdata BBs scene: in common with my peers I used my Beeb to run a bulletin board (The Rabbit Run) and it had a couple of hundred users. Other boards around the time included Chipboard (which ran on EBBS in Leeds), CARBBS-based bulletin boards such as Odyssey, Optix and Cyclone, and FBBS-originated boards such as CCl4.

Having rediscovered the original disks for my BBs numerous times and archiving off portions of the board to more resilient media than the 5.25″ floppies they’re on, the data’s nice and intact.

Now comes the fun bit. One of “those” nights in the pub set me thinking about how the BBs could be put on the Internet, in a similar way to CCl4 and Haven. However, I’d want to keep a nice clean delineation and not “taint” the system with modern technologies or developments such as GoMMC. Thus the idea of using VoIP, modems, Econet storage and original hardware came along.

We’d take a BBC Micro running the BBs software using a Dataphone “Designer” modem to answer (no Hayes modems around this time, remember?), and connect the modem via a house phone exchange to another machine which would actually dial the line when an incoming telnet connection was made. The Beeb setup would remain on faithful pre-1990 hardware, and it’d be a solid recreation of an original Viewdata setup. The Java Viewdata applet could be used or we could write a new one with proper aspect ratio, etc.

Last week, that led to another thought – if we could get one BBs up, why not get others going? There are archives of pages and messages hidden in lofts (there are a couple which I’ve got copies of in any case); so the idea of using an Econet to have a stack of Beebs with modems came about. Believe it or not, I think the hardest bits to source will be the non-Hayes modems (Dataphone Demon-2, Designer, Telemod, Pace Nightingale, etc.).

The idea’s still work-in-progress until I get the stuff running, but it seems that we could end up with a live “Acorn BBs museum” using original hardware and files.

Update on the ST506 Problem: Ian and Jules over on the BBC Micro maillist suggested that it was probably the stepper motor in the Winchester drive being ‘sticky’ – rotated the stepper arm a couple of mm seems to have sorted the problem out. I’ll let Google index this for the next person to have the problem 😉

<%image(20060711-beebs.jpg|120|106|)%>I’ve managed to source some Econet bits including terminator boxes and socket boxes. There’s now enough bits to get a basic level 3 fileserver and workstation up and running, plus the ANFS ROMs which Chris has done for me will go nicely in the Masters together with the Econet modules which will arrive this week. I can then turn my mind to the dialup interface and the modems – probably the first BBs which will go up will be The Rabbit Run (since I wrote a lot of the code and sort-of understand it). I’ll do some touting once we’ve worked out the icky bits of connectivity – we’ll have a couple of Archimedes ones up too.

Paid a quick trip to Maplin after work to get some shielded 4-core cable, and got blank looks when I asked what the mutual capacitance on the cable was. Took a few seconds then got asked “oh, you want speaker wire?” *sigh* They really have gone downhill 🙁

I also appear to have Z80 coprocessors coming out of my ears, where I really want 6502 ones. Pfffff. Anyone out there want to do a swap?

Update: The Winchester drive appears to have gone pop. More specifically (according to this tech note) the LED error code translates to “Index pulse not detected during spinup”. So, time to find another drive, which will be a bit of a sod: to this end I’m now looking for a Miniscribe 3438, or at least some other half-height ST506 (pref. RLL) drive.

I finally got off my arse this morning, fired up the RiscPC and reconfigured its IP address.

End result, Haven (my old Viewdata BBs) is back and available via a Java client again. Taste that 40-column retro Viewdata goodness here, but don’t expect any updates – the Sysop’s Bulletin still thinks I work for Mailbox, and that was at least 4 years ago.

Those of you who are really retro can probably telnet to haven.jml.net:23 with a Viewdata emulator such as Hippoterm. The truly retro will have to wait until I’ve got it hooked up to a phone line, but that’s probably best saved for the BBC Micro madness 🙂

[ Those of you who don’t know what the hell I’m on about (usually because you whippersnappers are too young, this was during the 80s dammit) can find more about Viewdata on CCl4’s site – be enlightened at the marvels of escape codes, attributes, and giant telephone bills ]

I did say yesterday that I’d post more once I’d stopped swearing. Truth of the matter is that I haven’t stopped swearing in the slightest.

There’s a BBC Master 128 in my collection: it’s almost 20 years old to give it its due, and the CMOS battery pack inside had badly corroded so I replaced it. I’ve also made an attempt to repair one of the shift keys – the internals of the keyboard switches are prone to oxidisation but the entire damn lot of spares I had were oxidised too. How tedious.

Anyway, as mentioned yesterday I’d picked up an internal 65C02 second processor, which upgrades the 128 to the Turbo model and enables it to run the Level 3 Econet fileserver software. I also picked up the 8-bit IDE module from JGH and set it all up. That’s where the troubles began. You see, things like the IDE module and the GoMMC rely on patched filesystems and external utilities for things like formatting, firmware upgrades, etc. which is all well and good, but a pain in the arse if you’ve only got 5.25″ drives attached to the Beeb and the only floppy drive in the house which will work on a PC is a 3.5″ one.

So, thinks I, I shall be clever. I pulled the RiscPC out from its resting place and connected it up to the sole SVGA LCD sitting in the house. Nothing. Nada. Not an electronic sausage. The RiscPC is just too old, and the LCD panel is just too limited in its range – fine for a Windows box, crap for something which requires some sort of odd sync. I swear for a short space of time, and then remember I used to do transfers like this using serial leads.

Problem #2 occurs – the BBC’s serial port requires a 5-pin domino DIN connector, which aren’t made any more. After fighting with a pair of pliers, I manage to construct a 5-pin domino connector and Google for a suitable pinout, selecting the first likely candidate. Soldering iron gets fired up, and I start building the cable (bear in mind it’s easily 5 years since I soldered anything, probably 10). At this point, there’s a huge crack sound from the garage. I investigate, and smoke is coming out of the Master 128’s switched-mode PSU. I turn it off, and then back on to be greeted with the familiar ‘beep boop’ – doesn’t seem too bad, so I leave it switched off while I go back to finishing the cable, which takes me about another 20 minutes.

Return to the workbench, start up one of the BBC B machines with ADFS in. Find the old Comstar-II ROM. Connect the serial lead. Try to talk to it. Nothing. I return to the laptop and Google some more to find out the relevant *FX command to change baudrates. In that time, I discover Angus Duggan’s serial cable pinout with a completely different set of pinouts. I swear once more, fire up the soldering iron, desolder my connector and resolder it with the correct pinouts. It works! Hurrah! Much celebration!

The celebration however is shortlived as I discover that Comstar’s XMODEM file transfer routines are shonky enough to barf at things over 200kbytes in size, and can’t do flow control properly so there’s retries every time it saves to floppy. So off I go to dig in the floppy disks eventually returning half an hour later with a copy of Gareth Babb’s term application, which does the job and at 19200bps as well. I now have, er, a 5.25″ floppy with all the software on I need. Time to plug in the IDE drive to the Master 128, and get it going. I duly do this, and find that I can no longer access the floppy disk. Bollocks. So it’s either the floppy or the hard disk. Further investigation reveals that the 1MHz bus doesn’t actually think it’s got anything plugged into it. There’s a tale involving the GoMMC as well, but that’s pretty much got the same level of success.

I’m starting to think that:

• The BBC Master 128 is so knackered that the 1MHz bus is blown, and it’s doing odd things internally.
• The MMC card I have for the GoMMC isn’t compatible “enough”.

So, I’m on the lookout for another Master 128 (got one in the loft? Give me a yell please!), and Kieran’s bringing round an MMC card he has kicking around the place.

I just keep thinking of the satisfaction I’ll have when it’s all working, and my mind inevitably wanders to the thought that I haven’t yet worked out a reason why I’m doing this.