Refurbishing the BBC Master 128

[@TheChloeRed]

The reason the machine pauses when the CMOS is reset is ADFS copies the current disc's catalogue into memory. This also means you need to dismount ADFS discs before ejecting. DFS doesn't do this, hence the recommendation to change to DFS to reset the CMOS settings. It just speeds it up. Traditionally on Acorns, DFS is used on 5.25inch drives, and ADFS on 3.5. This isn't fixed, just how it normally went. ADFS is a hierarchical file system, so also supports hard drives.

[@hjalfi]

ADFS is pretty nice as far as 8-bit hierarchical file systems go --- it's a bit slow, and doesn't support fragmented files, but it's pretty light on resources --- but I have no idea why they made it automount the disk when the file system is initialised. On a system like the Master which is intended to be able to operate from cassette, having it just hang on boot is so not helpful, even if you _can_ change the default file system. Very odd.

[@TheChloeRed]

@@hjalfi It only does it on the none-ARM machines too. When you get to Arthur/RiscOS, it mounts on selection, not boot. But also ADFS on anything 8bit but a master is a PITA. Because that storing of the catalogue in ram moves page up by around 3.5K, from &E00 to &1900 IIRC, so _tonnes_ of electron software won't run with a Plus 3 due to lack of ram.

[@Soruk42]

@@hjalfi You could switch to ADFS without mounting the disc with *FADFS.

[@hjalfi]

@@Soruk42 Dammit! Someone should have told me that forty years ago. (Also, why isn't this the default?)

[@tonystanley5337]

Re drying - in Electronic manufacturing we sometime bake older boards to remove absorbed moisture prior to any reflow work (>6 mths you should always bake electronics, otherwise you get blistering). For wet electronics post cleaning and drying I usually bake them at about 70-80C in the oven for 6-12 hours. Drying for reflow is usually 120C for 48hrs. You need to run defender or elite and of course write your own program, interface with the I/O ports.. Try making a capacitance meter using the analogue joystick port and cassette controller relay (if the master has one I did it on my BBC), all accessible via basic.

[@wewillmakeit3615]

A little word about washing pcb's in water: It is not a problem with old hardware as there are no surface mount components. But with the more modern stuff it can give you some problems. The SMCs are laying flat on the board, water is sucked underneath those parts by capillary force and is not able to evaporate for a very long time. You then get shorts or lowered resistances or corrosion, which is a problem. In those cases you have to bathe the pcb in 90% alcohol which is able to suck the residual water out underneath the parts and then evaporate. I had a small business around that fact in the early 2ks, repairing waterdamaged Nokias, when they were still a thing.

[@domramsey]

Please do a part 3 and spend some time exploring it. Also.. more cleaning videos please! 🙂

[@Jody_VE5SAR]

+1 the cleaning videos. I was wondering if the RF module would retain water and be hard to dry out. Sad to see it oxidize so much.

[@johnbarleycorn_]

The *HELP command when it stops, press shift and it will carry on. You can also do "*HELP " and it will give you the commands for that ROM, e.g. *HELP ADFS will give you a list of all the ADFS commands. For the cursors, there are actually two. When you press a cursor key they separate and you control the underline form of the cursor. What you do with this is move the cursor to a position on the screen then press the "Copy" key to copy the text. The idea is that if you'd typed "PRNT" instead of "PRINT", you move the cursor to the "P", press copy twice, press "I", then press copy twice and you've got "PRINT". It's the editing process for the BASIC program. It's also a good reason to check if you've got a working "Copy" key! View is a word processor built into the machine that can be accessed through the "*VIEW" command (and *BASIC to get out again). Pressing ESC switches between the editor and the command mode. Viewsheet is a spreadsheet, SRAM manages the additional 64k of memory, and Terminal is pretty self explanatory. This has the details of the mod to get colour on the composite output: www.beebmaster.co.uk/CompColour.html If you're looking for ROMs and documentation, there's a pretty good collection here: mdfs.net/ There's an archive of games here: www.bbcmicro.co.uk/

[@mrab4222]

Ctrl+N turns on page mode (pause after one page of output) and Ctrl+O turns it off.

[@parkamark]

44:30 When you split the cursor, use the COPY key and that will copy the character that is currently on the thin cursor over to the block cursor and advance both by one character. This allows you to hold the copy key to duplicate entire strings of characters as needed from elsewhere on the screen.

[@memsom]

The point of that was to edit lines in basic.

[@OneOfThePetes]

Ah you beat me to it! :)

[@DerIchBinDa]

That is the same way it works on the Amstrad CPC for people not knowing.

[@memsom]

@@DerIchBinDa yeah - I believe Amstrad “borrowed” it from Acorn. Amstrad had quite an advanced basic which I guess was also inspired by the BBC.

[@DerIchBinDa]

@@memsom I believe that immediately as I see the BBC computers were so good designed they for sure "borrowed" some ideas. 😄 Incredible how the UK was so far ahead in computer design and software and all that is left nowadays is Arm... sad tbh.

[@gazzythomas]

Well done Adrian. These machines were really the British Apple II. Such an open architecture for the time

[@stevekgoodwin]

BBC Basic is worth dipping into, structured programming including proper functions and inline assembler. It was very common for games to have a BASIC bootstrap app that would load a binary and execute it. Which is where I got into programming way back when, hacking the encryption routines so I could copy games. FWIW some of my favourite games were Rocket Raid, Thrust, Castle Quest, Exile (the encryption for this was insane, I never cracked it) and, of course, Elite. Great video, not enough BBC Micro content on the web.

[@jaycee1980]

You absolutely have to play Chuckie Egg :) For video, rather than try to work with the composite, you could use the TTL video output. It should be somewhat similar to CGA signal wise and should connect to a CGA monitor with the appropriate cable

[@fantummenelkinstruments1959]

Oooooh I remember Chuckie Egg!

[@cmjones01]

The Beeb's RGB output will drive a CGA monitor but you need a small amount of electronics to separate horizontal and vertical sync from the Beeb's composite sync signal. I made a little box to do this, back when CGA monitors were easier to find than BBC-style ones.

[@jaycee1980]

@@cmjones01 you can also get the horizontal/vertical sync signals internally, from pins 39 and 40 of the 6845. I'd buffer them first of course...

[@cmjones01]

@@jaycee1980 yes. I built a outside box (only one transistor and a few passives to separate field sync) because I wanted to use it with various Beebs without modifying them all.

[@shawty_ds]

If you've any particular questions Adrian, I'm happy to try answer them for you, and if not I'll most likely know the right people to ask :-) Loving the care you given this machine and the restoration you've done on it. I've been involved with Acorn Hardware since the early 1980's, and at one stage in my career even did a small bit of contracting for various Acorn software companies. While I no longer own any physical hardware, I do keep in with the community, and the various emulators, and I still have quite a shelf full of original Acorn Manuals and books on programming the machines. Feel free to shout me if I can help.

[@chrisplatts2607]

I’m astonished that you have a Beeb that was actually used at the Beeb and for Ceefax publishing, no less! One day I’ll be brave and submerge a PCB in soapy water! I have *insanely* hard tap-water down in southeast England though, so I’ll be sure to give a distilled-water rinse after. And thank you so much for delving into the faulty keys! I’ve got an Electron with some dodgy keys which I’ve been putting up with. I’ll definitely take another look at that and check those odd little pins.

[@adriansdigitalbasement]

Yeah basically, remove the switches from your Electron, unscrew the legs and then use something like an X-acto blade to scrape off any tarnish.. and then use something like Deoxit to remove any other tarnish. Perhaps metal polish would work too? The computer has been working great ever since and it's been a couple weeks since I did the keyboard work.

[@Error6503]

All of the raw OS commands are available from BASIC, in fact from any language, by prefixing with "*", so "*configure" at BASIC is exactly equivalent to "co." at the OS prompt (the BBC used dot to shortcut keywords). *help is showing what's installed in the ROM sockets, not necessarily what's running. The BBC used bank switching between #8000 and #BFFF to allow up to 16 ROMS in the same memory space. When using the DFS/ADFS the OS calls are at the top of memory which swaps out the language ROM for the duration of the disk routine. IIRC View was a word processor, ViewSheet a spreadsheet application and Terminal a dumb terminal emulator for connection to mainframes ! The Master had 64K of RAM mapped into 4 ROM locations, this allowed a special version of BASIC relocated to lower in memory to see 64K of user data instead of the maximum 32K for the ROM version of BASIC.

[@hjalfi]

... to get the disk catalogue, do `*CAT`, which can be abbreviated all the way to `*.`!

[@Soruk42]

That special version of BASIC is BAS128, and is on the BBC Master Welcome disc and tape. The program code runs in "normal" memory, and it uses the "Sideways RAM" as if it were a contiguous 64K block of memory. With all the bank switching going on, it was a bit slower than the "normal" BASIC.

[@chrisplatts2607]

Oh! Just a thought - it’s really easy to add SD card storage to a Beeb. Hardware-wise, all you need it one of those dirt-cheap SD card boards for Arduinos and some ribbon cable to connect it to the User port. Then burn MMFSv2 to an EPROM and you’re away. I can recommend the BBC port of the Bad Apple demo. I had no idea the Beeb’s (quite terrible) sound chip could do so well.

[@adriansdigitalbasement]

I know a ROM exists to interface directly to it -- is there a simple open source project I can build at home?

[@SimonEllwood]

​@@adriansdigitalbasementMMFS is maintained by Hoglet of RGB2HDMI fame and is on GitHub!

[@amostake]

If that had been me, I never would have guessed that the pins themselves that you pulled out of the switched, were actually the contacts for the switch. I never would have thought that. That is such a foreign design concept to me.

[@JamesE707]

It's been more than 30 years since I used the BBC B/Acorn Electron/BBC Master that I've forgotten the commands .... ha ha! I used to know nearly all of the commands, and now I only recall basic BASIC commands etc. BBC Basic can also be obtained from R.T.Russell who wrote a very fast emulator for the PC. Thanks for this upload and the time you put into this, great memories!

[@snafu2350]

32:02 for rethreading anything without cross-threading, give a half-twist /backwards/ with a little pressure until you feel the 'click' of the thread re-engaging with its original cut. This may seem a little strange & awkward to perform at first, but with only a little practice you'll soon get the hang of it until it becomes a habit - a good one to have, as (esp with eg self-tapping screws into soft plastic) it'll not only avoid cross-threading but won't cause the soft plastic threads to fail due to overstress

[@dhpbear2]

Yes! The 'Fran' method :)

[@HwAoRrDk]

Brings back memories of playing 'Frak!' on the BBC computers at school during lunch break. That game was stupidly hard due to the dreadful frame rate and input lag. We preferred playing it on a Master because it seemed to run a bit faster on those. Never completed the game even though it only had 3 levels. 😅

[@pitmatix1457]

There was the notorious hack version of it going around too. It was a bit naughty. ;-)

[@frankdaly2016]

​@@pitmatix1457Yes there was. It was amusing 😂

[@Darxide23]

It's crazy how those key switches work and how easily serviceable they are. My mind was blown just by the legs unscrewing like that without disassembling the entire key switch itself.

[@hjalfi]

That hang at the end with the Welcome Disk is worrisome. Pressing BREAK should never do that --- it's wired up to the 65c02's NMI line, and should always reset the OS. There could be a hardware fault. Also, if you do *ROMS you'll get a list of all the installed ROMs on the system, which should should what that EPROM is. *EDIT is the text editor; use the overlay strip you found to get at the commands. There is _also_ a word processor, *WORD (it's called View and it's functional but primitive). Once in it, use ESCAPE to toggle from command line mode to edit mode. There's a spreadsheet, too, called ViewSheet --- use *SHEET to enter.

[@timkirby5179]

One of my first jobs was repairing BBC computers. I am reminded off a computer that was brought to us that had (we think) 240v put through the Video in connector. After two days of work - that included replacing the (6502) CPU that had a crater where the silicon used to be - I had the Acorn Computers, BBC Computer shown on screen, though not steady. The memory of the fault finding - for example finding a snapped chip because I felt heat when my hand was near - and fixing needed -running entirely new tracks because the copper on the board had vaporised - over those two days makes me grin even now. I'm a teacher now and I some time try to explain the students the enjoyment that can be found from fault finding. They are rarely convinced. Thank you for this trip down memory lane. BTW. If it will not load from tape it will be the little 8 pin chip just by the tape socket - 40 years ago I could have instantly told you the chip number!

[@falken_gt4]

This brings me back. I used the BBC Master and the B model at school. We had a computer lab that had a Master with optional ROMs and a Hard Drive, this was connected to a fleet of Masters and B models using Econet. We learned how to do BASIC and how to make Teletext pages as part of the class. In Technical Studies class we used them to control robotics using Technic Lego and Fischertechnik which had controller boards that plugged into one of the ports underneath. Cut to a few years laters and I work for the Local Authority in IT and was on the tail end of them being in schools in the late 90s, a common task was desoldering and replacing the keys, we had bags of spares! Our workshop had a few CUB monitors for working on them. Loved the Master’s keyboard.

[@BlameThande]

When you mention using them to control robotics - I was surprised and depressed at a conference recently to see people in suits wowing over a robotic arm that could write their name, which was no more advanced than what we had with the BBC Micros in primary school in the 80s!

[@falken_gt4]

@@BlameThande haha, yes. I made a pneumatic 4 leg flight simulator that could run to a preset program or could be controlled by a pneumatic joystick 🕹️

[@garthhowe297]

Once again your videos provide a great resource for those wanting to keep retro computers running. I never would have guessed that a key switch would have screw in pins.

[@christreen7193]

Washing PCBs... At university, while my classmates were using BBCs, I was the one Speccy guy. Wrote my final paper on it, taught myself Z80 machine code, etc. Imagine my horror one day to come back to my student hovel to find my door broken open and water pouring through the ceiling following a burst pipe in the room above mine. The wet mattres and clothes wasn't my biggest concern, or the sparks around the light fitting... my poor Spectrum 48K was full of water. My landlord gave me a stack of 50 pence pieces to put in the gas meter and I ended up dismantling the Speccy and drying over the gas fire for a few days before risking a power on. It still works to this day 😂 Thanks for another great video!

[@malcolmhutchison]

The COPY key is for editing lines in BASIC - you use the cursor keys to move the [copy] cursor, then press the COPY key to copy the character under the copy cursor to the input buffer

[@cashawX10]

This was a BBC Micro feature that I still miss to this day, used to make fixing code so much easier...

[@garethdodds]

Thanks Adrian. This brings back so much nostalgia for me. My first computer was a BBC Micro 32k. I used to dream of owning a master.

[@joneggelton]

Me too. These machines are a very special part of growing up in the UK in the 80s. Just seeing the beige/black/red colour scheme brings it all back.

[@markwanklyn4195]

BBC Micro was my 2nd - had a ZX81 first - stupidly I sold my BBC (with monitor, 2x 5.25" 80 track drives, etc) some years back - missed it so got myself a replacement around 2017 and have four of them now plus a Microvitec CUB monitor and a SD card reader. Still have my original Kaga Taxan KP-810 dot matrix printer though

[@robertianhawdon]

From what I remember from my early years in first/primary school (1994-1999), what you'd call "elementry school", to boot from a floppy from the BASIC prompt was simply a case of holding SHIFT then tapping BREAK. However, it's been about 25 years since I used a BBC Master, so there's probably some things I'm miss remembering.

[@U2031]

I was going to post exactly this, Shift break would load from the disc and run it.

[@skonkfactory]

The RGB output on the BBC isn't actually TTL (only the synch signal is). You can plug it straight into the monitor used on the Amstrad CPC and it will work fine.

[@aerobaticant]

The BBC RGB output IS about 4V, for TTL monitor inputs. To get 1V into a 75 ohm input a 270R series resistor is recommended.

[@blackterminal]

Would you need some kind of adapter?

[@skonkfactory]

@@blackterminal Nope. Pinout is compatible.

[@mdpenny42]

Not sure if someone else has already mentioned it, but "?" is the BBC BASIC equivalent of "PEEK" and "POKE" (so "PRINT ?&70" and "?&70=0" will work); and "!" does the same for 32-bit words (rather than single bytes). (And, yes, "&" is the BBC BASIC prefix to indicate a hexadecimal number.) Also, "View" is Acorn's word-processor - use "*WORD" to switch to it; the "unidentified" key-strip is, I suspect, the one for "View".

[@Mincebert]

The Wikipedia page for POKE and PEEK covers how they work.

[@cmjones01]

and $ works for strings. BBC BASIC has byte, 32-bit word, and string pointers, which allows some really handy tricks. Want to write a string to memory at location &7C00? Just do $&7C00="Hello world" and it's done.

[@cashawX10]

For a short while in the late 80's you could download software and current satellite weather maps from Teletext if you had the costly Acorn Teletext adaptor, which I didn't but my school did and lent it to me. It was useless to them anyway as the TV reception at my school was really poor and you needed a rock solid signal to get accurate teletext reception.

[@chrisatye]

CEEFAX was amazing. In the UK, it hung around for years - it was easy to use, had recipes, quizzes, horoscopes, news, sports results - it was basically the next best thing to the Internet for a long time! The other TV channel in the UK - ITV - called it’s teletext service ‘Oracle’ for a while, before changing it to ‘ITV Teletext’. They were into advertising, so their service had ads - and you could book holidays on there as well. And the most famous page in the UK was Channel 4’s quiz ‘Bamboozle’ - I kind of miss those days. Great video - looking forward to the next one!

[@mogwaay]

Awesome work on the keyswitches! I have an electron keyboard that's mostly great, but the 7 keybis a little iffy, so it's fantastic to see how you removed and cleaned the pins to get them working well again.

[@david4368]

Just imagine if people had 10% of your enthusiasm. I look forward to your dedicated retro computer presentations.

[@miker252]

A few years ago I had a HP dc5800 SFF that was crashing either on boot or soon after. I spent quite a while switching out RAM, CPUs, Drives and Power Supplies and searching for bad capacitors without success. Finally, after watching one of your videos, I washed the Motherboard in soapy water and let it dry overnight and reassembled it with the original components. It has been working flawlessly ever since.

[@tb-cg6vd]

38:35 I hit the ceiling - I haven't seen that screen for 40 years but it's burnt into my childhood memories, far out! Thanks for that, never had a dopamine surge from nostalgia like that before!

[@ZenEmu01]

I love these machines. A lot of them had a tough time in schools and colleges, but they are built like tanks and the Tube interface is something very special for the time.

[@EnglishMike]

I can hardly believe it's been over 40 years since I took delivery of my BBC Model B -- about the only thing in my life I actually preordered. Had to wait months before it finally arrived, but it was worth the wait. Sadly, I sold it a few years later after upgrading to the 16 bit generation -- an Atari ST. The BBC was an excellent gaming machine for its time, and as others have already suggested, you should definitely have a session with Elite, perhaps the most famous game for the BBC Computer, and Chuckie Egg. David Braben, who co-created Elite with Ian Bell, is considered one of the most influential game developers of all time, and was a cofounder of the Raspberry Pi Foundation to boot. Elite pushed the BBC hardware to the limit, actually switching graphics modes mid-frame to provide high-res black and white wireframe graphics for the main display while using a lower resoution 4 colour mode for the cockpit control panel, not to mention programming an "open world" universe with two thousand unique star systems to visit and trade with in about 24k of RAM available for the game code and data. There's also some excellent versions of the arcade classics from Acornsoft like Snapper (Pacman), Planetoid (Defender), Hopper (Frogger), and Arcadians (Galaxian). The Repton line of games are also classics, and there's dozens more, too numerous to mention. It really was an excellent machine for its time, and while in hindsight the BBC probably should have opted for a cheaper design for its educational computer (e.g. from Acorn's rival, Sinclair) I certainly never regretted forking over 335 quid of my hard earned summer job income for it while I was a student.

[@jeromethiel4323]

Nothing wrong with washing a mobo. Done it with many machines, both old and new. I usually soak in alcohol afterwards to remove any water or soap residue. But then i let them sit for a couple of days, to ensure that ALL of the liquids have evaporated.

[@belzebub16]

2:23 Teletext is still fully operational, as it is part of the DVB standard, so most stations still provide it - really gives me 90s flashbacks.

[@Octojen]

With *help and some other things, its 'shift' to get to the next page. Loading from disk is usually shirt+break With the arrow keys, that confused you, you can hit the copy key, and it will copy whatever you have moved the cursor to. 'Mode 7' teletext is the classic start up mode, for classic feel. Disks where is heavy use, I'd not bother with tape. If you want to reset. and just hitting 'break' doesn't work, try ctrl+break. If you want to type basic, you can save some keystrokes, using the period. The interpreter will try and guess the rest of the keyword from the period. So "P." turns into "PRINT". If you want to see whats on the disk, type "*." which is short for "*CAT". If there was a basic program on disk, you can LOAD "filename". Or CH."filename". Scripts are *EXEC. Machine code *RUN. Pressing shif+break usually does '*exec !boot', which is usually a short script that just chains some basic program. What software... its a personal thing. Most would suggest running elite. Personally I enjoyed playing repton. I see you had VIEW - a respected common word processors, although interword was better. I typed a lot so i'll stop here.... i fricking loved the beeb!

[@annikajinx]

Yup ... CHAIN "filename" for running programs brings back such good memories as does *RUN "filename". Damn I wish I hadnt sold my setup. Ok I am off to find a BeebEm so I can play Elite again. I wonder if the bundled novella is online? I did always like an Iron Ass.

[@Psychlist1972]

Your excitement after fixing that first unthreaded switch was infectious. :)

[@SidneyCritic]

You can check the current draw on the CR2030 by putting the DMM probe on the battery, and pushing the holder side contact sideways with the other probe so the current passes through the DMM. It would be interesting to know the current draw on those old computers, because a modern-ish PC is about 4uA.

[@VoVilliaCorp]

seeing the key switches getting cleaned and working again was very satisfying

[@cosmo9882]

"P." for print. Awsome machine, thank for restoration. You can also just type "BEEP" also. The empty EPROMS are for stuff for eg a "speech chip", which sounded better than early google and iPhone. Good work with with the space bar they are a "bic" to get back on.

[@RetroBytesUK]

35:00 If you hold ctrl while pressing break, thats the machine reset sequence. Saves having to turn it off/on in most circumstances.

[@Gattancha]

This brings back some memories - I remember in the early-mind 90s our High School had 3 suites - 2 had these connecting to the ECONET network. The 3rd suite was kitted out with Acorn Archimedes A3000 which was the computer that introduced me to Lemmings - Not sure the teachers were happy that one though If ever Adrian get's the chance to, he really should get his hands on the A3000 as well

[@EgoChip]

Same here! I would play Lemmings on the Archimedes at school. That was when I wasn't playing Chuckie Egg and Killer Gorilla on the BBC! I was special needs, and the teachers let me do what I wanted as long as I got my work done.

[@Firthy2002]

LOL a school A3000 introduced me to Lemmings 2!

[@jameshare1848]

​@@Firthy2002 I'm glad I'm not alone 😂 the music in lemmings was amazing and it sounded the best on the Acorn

[@jameshare1848]

Also when you drag a window on the A3000 the contents remain visible. Windows couldn't manage that until several years later

[@belperite]

@@jameshare1848 Yes you needed the plus pack on windows 95 as I recall. We had a single A5000 at school along with an assortment of A3**, A4** and A3000s and I was amazed at how fast the A5000 was compared to anything else I'd used at the time.

[@ResurrectionRetro]

The star character is used at all prompts to run command. So *roms lists all the roms ( with their hex code). *co. Lang and then the rom nunber changes languages. *disc set it in disc drive mode *tape for tape mode *view takes you into the built in word processor. *sheet into the spreadsheet. There is a bunch of *commands.

[@argentas]

From memory, I think it was *word for the word processor (even though the word processor was named 'view'). *view was for viewing the screen of another BBC micro on the econet (along with *remote for taking control of another computer). This was all a very long time ago though so my memory may be corrupted!

[@Soruk42]

I fashioned a replacement battery for my M128 with a small lithium-ion cell, with the diode, and used a miniature USB to lithium charger module to take the 5V supply and charge the battery in a controlled manner. It fits in the side to the left of the keyboard where the original 3AA battery pack lay.

[@jameshare1848]

The BBC master was my very first computer experience. My infants school (in the UK this is for children 4 - 7) had one of these. It pretty much sat in the corner collecting dust until I became obsessed with it 😂 The teachers didn't really know how to use it apart from loading programs from one of the many many floppy disks it came with. Great memories

[@stephenrowley4171]

Ditto

[@twocvbloke]

Teletext was a staple of the 90s household, whether it was for news, weather reports, financial updates, or even games (Bamboozle on 4Tel being the best known), it was something often seen on our tellies back in the day, and for the names, Ceefax for BBC, Oracle I think for ITV (which later became simply Teletext), and Channel 4 had "4Tel", all the same basic standards, just their own names... :)

[@EmptyGlass99]

Ceefax/Teletext really felt amazing at the time. A very early taste of the internet. I've forgotten them now but until not that long ago I could recall all the page numbers for things I was interested in (401 for TV listing I think!)

[@budgiefish]

Remember the games on Ceefax? :)

[@almerian]

I still use 'Teletekst' every day in the Netherlands. Fist thing I check in the morning. 101 News, 601 Sports, 801 Football, 818 Football live scores, 703 Weather forecast today, 704 Weather forecast week, 705 Current weather measurements 730 Traffic Information. Only takes two minutes and I'm ready to start the day.

[@danielmantione]

@@almerian It is often the first thing I do after waking up, even before watching the morning news bulletins. The remote control is ideal when you are still lying horizontally.

[@beatadalhagen]

Re: CMOS battery. I re-used a 3-cell holder from an old pocket torch, placed into a 3D-printed case. And now that you mention it, I'm unsure if a 3V standby will work in my machine.

[@ANTandTEC]

I used to tepair these for schools in the UK back in the day. I had no idea about the pin removal and clean. Used to just replace the keyswitch. Of course they were readily available then, I had a big bag of them.

[@PaulsComputerEmp]

Growing up, BBC Micros were a common sight in UK classrooms until around 1989. Thanks for sharing your awesome BBC Master computer video! It was informative and engaging. Appreciate your effort!

[@csgowoes6319]

Absolutely, it was a wildly successful scheme in my opinion, it got me my first real contact with a computer and I never looked back, and I know this is true of a great many other Brits of a certain age. I did not actually pursue a career in IT in the end but I owe my computer literacy today to the Beeb to a great extent.

[@garymetheringham4990]

Im in the same place as you with regards using the bbc, only just got mine. i did use one at school but that was 40yr ago so starting from scratch also. btw there is a motherboard jumper to solder in if you want colour out on the composite connector, but an rgb cable will give amazing picture

[@GYTCommnts]

Amazing! That keyboard fixing shows how important is archiving information on Internet. One post on a forum can save you. It made me remember a time when I wasn't able to find why a pendrive was losing connection while copying files. I finally found a lost post that explained that some part on them couldn't keep up with some speeds for copying files and would fail. So I started to use "Ultracopier", that had in older versions a cool option to limit speeds and... Voila! Problem solved to that! I thought it was my USB ports and tried a lots of things (drivers, configurations on the O.S., and so on...) and it was just a low quality part on some pendrives that can't handle some transfer speeds for long time.

[@lemagreengreen]

A mention of Microfax: "An emulation of a Teletext presentation system. Includes the Viewer and Page Editor. Originally released by Acornsoft as part of their Living with Computers series." So yeah, entirely possible that this machine may have been involved in the creation of BBC Ceefax pages. Pretty neat!

[@kaitlyn__L]

I’ve got a very strong inkling this was the machine that made the programs which got loaded into the broadcast Model Bs, super cool! The “use the cart slot for ROMs not the ROM slots” admonishment made me think it must get a lot more use cycling round than the other systems. Which makes more sense for an editor, though it could also have been one of the systems running pages that were more frequently updated than the others perhaps. I seem to recall some pages only changed weekly, others daily, and a few hourly? I always assumed the latter were reprogrammed in-place, but with reliability in mind perhaps not!

[@andrewwright1200]

P. for Print. Print "hello" would be 13 bytes used, P. "hello" would be 9 bytes used, but would list as print "hello" as the P. converts to the mnumonic for print

[@50shadesofbeige88]

I love Ceefax and Night Owl. That's so cool.

[@lexluthermiester]

@Adrian's Digital Basement About washing the motherboard: It's not all that shocking. I do it frequently for very dirty boards. Wash it, rinse it, spray it with 70%IPA and blower dry it. Let it sit for a few days. It's a great way to completely clean a printed circuit board of any type!

[@Hoodlum045]

I went through school on these computers (primary school to highschool) there were books that we would get from the library and copy basic code from the book to create games on the computer. one hidden feature we found (bear in mind this was 30 years ago) was if you press shift and any function key then type it would change the colour of the text. (great for text based RPG) from memory 0 would make them flash.

[@hugosimoes5119]

Teletext is still in use here in Portugal since 1996+. Teletext made it's appearance in analog tv from antenna at the roof and digitally over cable tv, then analog tv got killed and now over dtv. Public tv station RTP and the private tv stations SIC and TVI have teletext service. RTP was the first tv station that launched it back in late 90's. It still has the basic layout and pages, and not much changed since then. Quite like 10 years later, they implented some sound-to-text functionality like when some tv news block is airing, the system would output *delayed* text at bottom of the screeen to the pages 888/885, but not really useful and some phrases make no sense. The teletext like you said, it offers news feed, stocks,.... additionally it can have tv schedules, sports schedules, football scores, weather, horoscope and other kind of stuff. The private tv stations SIC and TVI do have teletext but their pages are poor in content. They have or had a text message service over SMS. You send a message to the service and the message would appear on the screen and that made chatting to other people possible. I never used this service and I really don't know why people (lots) would use this service when IRC and Web chat were more affordable. Like many things in the past and nowadays... they get broken and outdated and unmaintained ... and teletext is no exception. Plenty of pages rely on the Internet for feeding and when the source pages are changed in layout, the teletext processing engine no longer works correctly. You can check the teletext using this link: www.rtp.pt/wportal/teletexto/

[@danielmantione]

In most countries in Europe, teletext remains very popular. Only a few countries (UK, Belgium) did stop with teletext. Here in the Netherlands, it is estimated that approximately 5 million people use teletext each day. Out of a population of 18 million, that is a lot. While teletext is outdated, with such popularity, you don't need to even start a discussion wether to continue with it, that is a no-brainer. A lot of people consult teletext via the mobile app though, rather than via the television.

[@RetroBytesUK]

Microfax was used in schools to emulate teletex. It had a viewer, which would load which ever page the use chose by typing in the page number, there was also an editor which kids could use to create their own teletex pages using, and assign them a page number. It was published by Acornsoft, which was acorns own software house.

[@Dukefazon]

European here: I liked TELETEXT when it was a thing, it was something from the future, before having access to the Internet :)

[@stevemann2662]

Hi Adrian. You have a couple of options when reading disks on the BBC. *. will read the disk contents. Shift+Break will run a bootstrap from the floppy if enabled. As well as the LOAD command, you also have CHAIN which will chain together a number of files on the disk using a primary load file.

[@andrewwright1200]

All the beebug magazines are scanned on the 8bs site, and vol 4 edition 9 has the launch of the master 128

[@danriches7328]

It all depends on the metals used in the keyboard switch pins but scraping them with a scalpel may allow the base metal, usually copper, to corrode again. I'd be tempted to use a tin plating solution on them to prevent them from tarnishing again. Just a thought, great video by the way!

[@Colaholiker]

Tidbit regarding teletext: At least in Germany, it was so popular, that some TV stations still offer it, even though analog transmission has long been shut down. You can either access it through the station's website, or, depending on how you get your TV signal, through your receiver. My parents use some IP TV solution, and their receiver still supports teletext. It was also the place where you could find what Americans call Closed Captioning if I remember correctly, but that was only available for parts of the program.

[@danielmantione]

It is like that in most of Europe. A few countries, like UK and Belgium did stop with teletext, but in most countries, teletext is still available and often very popular.

[@chubbyadler3276]

Something I thought about as you were installing the battery, is what if we tried to mount that CR2032 holder to the back of the case near where the switch is? Then it would just be trivial to replace or remove the battery as needed.

[@cmjones01]

A quick summary of how the command line works on Acorn machines. Unlike many other computers of the 8- bit era, they don't assume the presence of the BASIC interpreter to interpret the command line. The operating system (Acorn MOS in the Master's case) contains its own command-line interpreter. It implements a certain number of commands itself (I can think of FX, TV, MOTOR and, on the Master, CONFIGURE and STATUS). It will then offer the command line to any installed utility ROMs (a very popular way of extending the computer's capabilities - my favourite was Computer Concepts' Disc Doctor) to see if they understand it. If none of them accept the command, it's then passed to the currently-selected filing system. Different filing systems may handle it in different ways. Some, like the cassette filing system, have no concept of random access, so can't search for a command. DFS and ADFS have their own ways of looking for commands on disc, and the Econet filing system (NFS or ANFS) will likely pass the command line to a network fileserver for processing. If all these ways of interpreting the command fail, you'll see the error message "Bad Command". When you're at the BASIC prompt, it's obviously doing its own command line interpretation to process your BASIC commands. Prefixing a command with the asterisk "*" (read out loud as "star" in Acornspeak) tells BASIC that you'd like to pass the command to the OS. It's just like shelling out to a DOS or Windows command line on a PC. The idiom of prefixing commands with "*" was used in very many interactive programs, such as languages and word processors, as a way to give the user access to the OS. On a Master, if no language is present or the currently selected language ROM isn't actually a language (hence the "This is not a language" message) the OS presents a command prompt of its own, which Adrian used to configure the CMOS values. Incidentally, the BASIC language ROM only interacts with the hardware of the machine and the filing systems via the OS. It doesn't touch hardware itself at all. The Acorn machines are quite unusual in the clear separation of hardware, OS and its API, and language, and it's this architecture that makes things like adding a second processor via the Tube feasible. Think of the Tube as a hardware interface to the OS's API, and you won't go far wrong.

[@ihardcas]

It really was a bloody well thought out machine. Even now.

[@Wobblybob2004]

There's a jumper on the pcb near the BNC connector for colour compsite output. (it may not be populated) but your output quality will take a hit.

[@Drew-Dastardly]

Yes, that is how I wired my BBC B to get colour on my TV in the 1980's. Far superior to the RF modulator but nowhere near as good as the RGB output. A Microvitec CUB monitor wired to the RGB port is what Adrian wants for the authentic school computer lab experience.

[@ygstuff4898]

The technique for cleaning the key switches and the battery hack! Absolutely brilliant (and the battery hack supports a "system reset" method). I never realised how future modern the BBC series of computer was...if not for the IBM PC, this platform could have been the standard (or maybe the Amstrad CPC)

[@sokoloft3]

Those legs on the switches are really interesting how they can come out. Glad you where able to clean them and get them working again! Also to me the cleaning the plastics is very satisfying along with final assembly once you've fixed everything up!

[@stuartmcconnachie]

When in edit mode, press the COPY key that you didn’t know what it did earlier. The character under the flashing cursor will be copied to the input cursor (white square).

[@igorwollersheim464]

CTRL-BREAK does a hard reset. SHIFT-BREAK does a soft reset and tries to run the !BOOT file on the currently selected filesystem. You can also do CTRL-SHIFT-BREAK.

[@DarrenHughes-Hybrid]

Great video. Really cool fix on those key switches! Radical design, makes me wonder if they planned for that fix when they designed those key switches?

[@adriansdigitalbasement]

Yeah I wonder! Once I got the hang of it, it's much easier to service them than Alps SKCC switches from Mac/TRS-80/Apple II/TI99.

[@8bitwiz_]

I once found a Das Keyboard (one of those with the all-blank key tops) with "blue" mechanical switches, where something had clearly been spilled on it. I could even see the splash pattern from which keys were sticky. I tried a few things, but in the end I had to desolder every sticky key (about a third of them!), disassemble the key, clean the bits with a cotton swab, then reassemble and resolder. Then the fun part was realizing that the different rows of *blank* key caps were molded differently! It took me a while to get them all put back, but it helped that the key tops had mold codes inside.

[@wytsfrevsf]

Amazing, at high school "Computer Studies" class we had one row of Commodore PET's and a row of BBC Model B with printers, the teacher had the BBC Master! and it had Econet network and a modem! it was the only lesson in school I would not want to leave :) after the second year, things got more relaxed, especially if you had done all your work, you could play games, remember playing Knight Lore and Elite :)

[@Jenny_Digital]

I've spent many many hours writing software for my home-made robots on Acorn machines, the BBC Master 128 with 6502 Second Processor being one of my favorites. If the switch doesn't come back to life by just cleaning the pins (Which I do with a fiberglass pen whilst wearing nitrile gloves), then you can separate the two parts with a Stanley knife. Also, I'd take a look at the EPROM that's there to see what it is. Sometimes people take out add-ons and forget the EPROM, or mis-configure the jumpers on the motherboard.

[@jamesdecross1035]

Well, that was hard work… yet, I love the excitement you express all the way through that restoration.

[@hjalfi]

FOR GODS' SAKE PRESS SHIFT _attempts to breath calmly_

[@carlpettit7754]

The 15way D con on the back is an analog input port. I think it had 8 12 bit channels and a couple of digital input/output pins too.

[@nickolasgaspar9660]

I always give soap baths to all my boards and I have never had any issues. On the contrary , the scrubbing on two of them seems to have removed an invisible solder bridge thus repairing their issues (instability and crashes).

[@jokinboken]

Congrats on your success so far with this system - your persistence and troubleshooting is inspiring.

[@cashawX10]

It's decades since I used one, but when you typed *HELP to list the ROMS, it froze which sort of means that there may be a problem with on of those socketed roms. That command should complete back to a cursor. Also, your Welcome disk also seem to crash the computer back to a level where break wouldn't work, so I think you may still have some issues there. I also never saw a BBC Master running with a 3.5" drive, it was always 5.25" back in my day. But thanks for the video ! I loved the Acorn BBC micro series, in the UK it seemed like one of the only pro-sumer 8-bit machines on which you could do serious work. The BBC used them heavily from everything from sound effects to on-screen graphics. In the 80's and a visit to Jodrel lBank radio space telescope, I noticed it was all controlled by BBC Micros.

[@jamesthomas807]

There are still BBC's in use at some Universitys in the UK controlling ancient scientific equipment.

[@cshairydude]

The Master Compact had a 3.5" drive. But that was a particularly weird machine in several ways.

[@Zeem4]

The output of *HELP on the Master is scroll-protected, meaning that it's waiting for SHIFT to be pressed before scrolling the output.

[@elfenmagix8173]

Dirt does not hurt the motherboard other than being dirty? **SMH** Depending on where you are in the USA, in fact around the world, the particulate matter of dust varies, with some areas having a high concentration of Iron Oxide (Rust) in the dust. Rust is conductive, so getting rust dust between VIA and Chip Pins can short a logic board and even a POwer Supply. Other areas have high carbon, calcium, and salt (Sodium, Potassium, etc salts) can become corrosive when humidity hits it and you can an acid. So dust is very harmful to logic boards. You find a dirty board, yu need to clean it. Here in the North East Coast we have Iron Oxide and Salt in our dust , so our boards are getting a double shot or corrosion if they are left alone.

[@Zerbey]

I used to run the computer lab at my secondary school, one of teachers INSISTED on resetting the CMOS every time he used one of our BBC or Archimedes machines. I still have all the commands you ran memorized 30 years later.

[@aquilux-vids]

One bit of advice on avoiding cross-threading: push the fastener in as far as it'll freely go, then with a small amount of inward pressure rotate it counterclockwise until it clicks and drops inwards by one thread width, then without releasing the inwards pressure turn it clockwise a turn or two and you'll be engaged in the thread reliably.

[@croztech]

When you do *HELP (or in other circumstances) press SHIFT to scroll to the end of the list. My Master had a similar keyswitch issue, but in my case, simply tightening the pins by 1/8th turn fixed the issue. If you want to learn more about the Master and other Acorn machines, I'll be at VCF West in August !

[@raybarker]

Adrian, there *HELP command should return you to the Basic prompt afterwards, and an unmodified master should only have one ROM chip installed, so I suspect the bonus unlabelled EPROM is faulty and locking things up when it's queried. Edit: Also, the RGB din socket on the rear of the machine outputs TTL RGB, so it should be relatively simple for you to make up an adapter for capture or for one of your many compatible monitors. Alternatively, it's possible to do a fairly simple color mod for composite - the Rev.2 board has a jumper link for this, but this looks like the Rev.1 board. I don't really recommend it though, as it introduces the usual color artefacts. No real point using tape loading unless you want the retro waiting experience - The BBC disk filing systems were designed to support anything from 8" SS/SD through to 3.5" DS/DD, although original-flavor DFS does it in a slightly weird way - a double-sided disk will be treated as two separate drives numbered 0 and 2.

[@theoriginalbabycub]

The MASTER came with all the ROM software shown as standard, split across more than one rom. bASIC for example is contained in a ROM of it's own as is the MOS afair. The pause was to allow the user to read the info before the user presses the shift key to show the next screenful of command output.

[@raybarker]

@@theoriginalbabycub wrong on both counts. The BBC Micro had separate 16k roms for the OS, Basic, DFS, etc, but the master came with one 128k rom with everything in it. The pause you describe is an option turned off by default, activated with *CONFIGURE NOSCROLL and the default behaviour is to dump all text to the console and return to the prompt. However, ROMs with no help text (or an equivalent fault) do lock up the console instead, as it waits for a text return that never comes.

[@raybarker]

It's possible the ROM in socket IC41 is the ECONet ROM, if so it should be moved to the slot above and LK18 set east, if it's currently set east that's a ROM/RAM collision. Moving the ROM to socket IC27 and making sure LK18+19 are set east will free up maximum shadow RAM, which the welcome disc might be attempting to use... either way, maximum compatibility.

[@Zeem4]

​@@raybarker The *HELP output is waiting for SHIFT to be pressed. I've just tested this with the jsbeeb emulator, the output of *HELP is scroll-protected regardless of the settings.

[@Soruk42]

@@raybarker NOSCROLL is the option to choose whether or not the cursor would wrap to the next line after putting a character in the rightmost column, without this you can't PRINT a character in the bottom right character cell without the screen scrolling up a line. The SHIFT-to-scroll effect is always used on *HELP but is switchable for other output using VDU14 to enable and VDU15 to disable.

[@jensschroder8214]

Teletext was a system broadcast in the blanking interval of the PAL signal. So when the tube beam of the screen moves from the bottom line back to the top line, there are invisible blanked lines. There the one-way digital signal was inserted and broadcast. The recipient collects the data and creates the pages from it. There is no return channel. There were also various national systems that worked via modem and had a return channel to request data. These costs for the telephone line, in contrast to teletext, which only requires television reception. Both systems were based on ASCII characters and a few predefined graphic characters. In some cases, the character set could be switched, or individual characters could be predefined. Or double height or blink of text.

[@supralapsarian]

Great work as usual. Thanks for taking us along for the ride! I know you’re not in a hurry to exercise the socket, but pulling the EPROM would be an easy way to tell what’s on it. It’s funny, at one point I found myself covering the EPROM with my hand when I walked into daylight. “Tell me you’re an OG Geek without telling me you’re an OG Geek!” 🤣

[@Soruk42]

Do *ROMS and see what shows up in ROM socket 8. 0-3 are the cartridge sockets, 4-7 are either Sideways RAM or ROM sockets (selected via a jumper), 8 is a 16K socket by itself, and 9-15 are in the Master OS 1Mbit ROM.

[@RyanMercer]

This was very satisfying.

[@LAGoodz]

I programmed these at school in 1980’s. Literally every British school had a couple of these. BASIC was such a good foundation as a developer in my career.

[@trickysoft]

Great video, I'm so glad that your perciviered with the keyboard. I love the affection you have for everything but it is especially good to see your enthusiasm for this British classic. If you want to see what a master can do, try and bitshifters demo or their Prince of Persia and Stunt Car Racer ports.

[@koenlefever]

47:19 VIEW is a word processor, ViewSheet is a spreadsheet.

[@agranero6]

About washing the board in production: my father worked on a company that made VHF transceivers used by police, fire department, etc. They washed the boards at the end, but it was done with hot IPA (scary, I know). In fact I saw that once when my father brought me with him to work. But some modern micromechanical devices can be damaged by that like acellerometers and gyroscopes (ask me how I discovered that).

[@davidblake6889]

Back in 1986 in the UK, my company used BBC Master computers as Teletext editing terminals. I helped to write the code for this in BBC Basic. I actually got my job with the company from a job advertisement on Teletext. I do remember seeing the error message 'This is not a language' pop up when the CMOS battery went flat. The main work of the company was to provide the platform to allow TV companies to insert the Teletext stream onto the TV signal before transmission using DEC main-frame computers. This was back when there were only four TV broadcasters, all of whom used our equipment to generate and insert Teletext. There was an attempt to get Teletext over to the US of A. Unsuccessfully, as it turns out, but there were NTSC TV's produced that had a custom Teletext decoder in. There were fewer lines available in the NTSC VBI compared to PAL, so the maximum data rate on NTSC was lower than that for PAL. This did not help the cause much.

[@thisnthat3530]

From memory when I used the model B back in the mid '80s: CTRL+BREAK is a "hard" reset (doesn't always work), SHIFT+BREAK will try to boot from floppy.

[@MikeLynx]

This is wonderful, Adrian. I have encountered all the same keyboard problems on my Camputers Lynx computer (a British Z80 home computer) - which uses the same Futaba keys. I assumed I'd never be able to source replacements key switches - but now I'm excited to have a go at restoring the ones I have. So far, I've only used the contact cleaner/million presses approach (with some success - although with flaky results), but cleaning the pins seems like a much better solution. Thank you! 😀

[@igorwollersheim464]

* sends the to the MOS rather than to the current interpreter (basic or pascal)