Prestel & ViewData Services

In the UK back before the internet arrived there was a system called Prestel that provided various online facilities via a ViewData interface. This was similar to the Minitel system used in France and was closely related to Teletext.

Here is my Minitel terminal all setup to test my dial in gateway and connect to Level 29 BBS.

And here it is logged into Level 29 BBS. Notice the screen size is very restrictive due to the 40 column width compared to most ASCII terminals that have 80.

Micronet 800

As part of the Prestel service large customers could rent pages (known as frames) or the Prestel mainframe could hand off to an external system to provide other services.

One of the most popular services was Micronet 800, it provided chat rooms, multiplayer online games and message boards about various topics.
It was called Micronet 800 due to that being the entry page number provided by Prestel (you entered 800 to get to the main page within Prestel). 

The main problem with connecting to Micronet / Prestel was that you needed a modem, most home users of the time didn't own a machine with a serial port so in an attempt to get more users Micronet provided a package for the Spectrum. As the Spectrum 48k did not come with a serial port and couldn't display the resolutions required to show the ViewData frames this was a problem. Micronet got round this by providing a modem with built in ROM and hardware to update the Spectrum so that it could use the service.

The modem sits nicely under the Spectrum and connected to the bus at the back.

Modem Functions

When you connect the unit to the Spectrum it patches the ROM to load the Micronet code.
This gives you get a nice splash screen when the machine is turned on.

When pressing a key you are returned to the main system menu.

There is a mode for automatically logging onto the service (this remembers your ID number and enters it at the relevant prompt).
You can save frames, store programs and check the mailbox. The system also allows you to drop back out to Basic so that you can use the Spectrum without having to disconnect the unit.

Selecting log on asks for you ID and then gives you this screen.

At this point you have to manually dial the number to connect the modem.
When you hear the tone you flick the switch on the front of the unit to go online.

Problems Connecting

As the unit is designed to connect to a ViewData system at V23 (1200, 75) it does not have the modern modem facilities such as auto-bauding. It expects the other end to be the same. When trying to connect to Level 29 BBS we hit the problem as the modem on the other end is using Bell protocols and we are using the European CITT ones. The main difference being the tone frequencies that they use.

My modern modem has an AT command to switch modes but will usually just figure out the other ends requirements.

As we don't have that option I altered my ViewData system dial in gateway to connect to Level 29 via telnet. This allows me to dial my machine locally and the software then connects to the BBS via telnet does any character translation required and passes the data back to the Micronet modem.

Connected To Level 29 Via The Gateway

When I used this in my office it worked fine, I could type my user name (with a little bit of effort as the keyboard is a bit awkward on the Spectrum) but my monitor wouldn't keep the sync with the Spectrums video output and the image kept rolling. I then moved this downstairs on a very long telephone extension so that I could use the TV.
I think that something was getting messed up as the keyboard was not sending the correct key presses back to the gateway.

Anyway you can see the main login page that we are connected to. The Minitel terminal in the office works perfectly with this so I think I need to sort a shorter telephone extension cable out and try it again.

KryoFlux Imaging Machine

So putting one last push to actually get something done.

Got the machine i'm going to use for parts to make my KryoFlux imaging system.
The idea is that I have a single machine for taking images of floppy disks so that I can start on the task of imaging the large quantity of Acorn software that I have in my collection.

The machine will have both 3.5 and 5.25 inch floppy disk drives and will copy all images to my NAS storage or USB.
I will initially RDP to the machine to take images of floppy disks using the KryoFlux software but when I have the time I want to create a remote front end so that all I need to do is insert the disk and it will image and create the appropriately named files.
So that I am keeping the full copy of the disk I will store both the KryoFlux raw data and a image suitable for use with emulators. Any disks that are copy protected can then be re-written using the KryoFlux raw data.

Donor PC

The donor machine is an intel Core 2 duo PC, this used to be my main machine back a long time ago and has now just been in storage doing nothing.
Due to the case being a full tower one I want to move the motherboard to a new desktop case that will fit under my desk out of the way.

The machine had a pretty good graphics card at the time but this is now pretty obsolete compared even to a lot of embedded chipset graphics processors.

Extracted the motherboard.

Assembling The New Machine

To get the board into the new machine I had to remove the extra funnel for the processor fan and take out the filter that is fitted to the new case as the fan goes right out to the case lid.

Had a spare internal SSD with adapter kicking around from another project.

Fitted the KryoFlux into this space, will fit it properly but need some longer floppy drive cables and more power for the 5.25 inch drive.
The KryoFlux needs to be plugged into the USB, I may rob a USB front panel from a case to use internally.

All assembled in the case.

The 2 floppy drives for archiving.

Things To Do

Need to sort out the floppy cable and either make one the correct length or get one of the nice round ones I have in storage. Not sure if I have one with a 5.25 inch drive flat connector.

Currently installing the operating system so that I can actually image disks.

OS is now installed and I can remote desktop to the machine so that I don't need it connected to a monitor to use.

Fix the KryoFlux in properly (I have some PCB stands somewhere) and fit an internal USB to the machine so I can connect the KryoFlux without any external cabling.

This now has an internal USB header on the board which connects to the Kryoflux.

Image all of my disks (this may take a while).

Started this but its going to take a fair bit of time.

Goodbye Retro Challenge...

So this is the end again for another Retro Challenge, as has been common in the last few challenges my 11 month old has got in the way so I've not really got a lot done.
I am happy that I've manage to do some of what I set out to do. Mainly sorting my storage locker so that I can easily access machines and other stuff so that I can start to clean and fix them one at a time.

Enjoyed looking at everyone's blogs and hope to see you all next time.

A Slow Start...

Well its already taken me most of the month to get nowhere but I finally found some time to sort out some of my kit in the storage locker.

There were several things that I needed to do before I could start on sorting machines out, firstly I needed to sort out the stuff that had just been dumped in the lockup.
Once this was done I could move around and access things much easier.

Boxes

A lot of my stuff was moved from my house so that we could prepare it to be rented out.
These boxes contain all sorts from Xmas decorations to various selections of Acorn stuff such as my collection of AcornSoft titles and various other bits that need sorting out over time.

The red boxes below are old boxes I moved from my previous storage locker, they have seen better days and are being replaced by the clear stacking ones instead.
They currently contain stuff like my Sega Saturn collection and various cables etc.
Unfortunately they were blocking the door of the unit so I had to wheel them out of the way.

Building Shelving

I have already bought several  cheap shelf units from IKEA and installed them to hold some of my machines.
After removing the desk that was in the unit I decided that I could fit several more so built 3 more units.

Moving Stuff

Once I had installed the shelves it was time to move some of the hardware that has just been stacked in the middle of the unit.

I spent most of the day moving hardware around, sorting out where everything should go and designating shelves for certain machines.

Risc PCs

Here are most of the general Risc PCs I own, there are a few floating around but most are on the shelf.
I also have several boxed ones in very good condition of which one is mine from university which I recently found the invoice for. It cost me £1118 in 1997.

A7000s

Some of my A7000 and A7000+ machines. The others are currently stripped down due to batteries being removed.

A3000s, A3010s and A3020s

A few A3000s and a mixture of A3010s and A3020s.
I opened these all up back along to remove the batteries, they all need cleaning properly,

A few BBC Masters in here as well, most of my BBC Masters are currently off site where they are having their caps replaced.
There are also a few more in various boxes, these probably need to be moved to their own shelf later on.

Archimedes

Various models of Archimedes. I even have the disk only 305 version, most of these however have hard disks.
I had to put these on the bottom shelf as they are really heavy and I was afraid they were going to make the shelving fall over.

Phoebe & R140

Here are 2 of my rarer items. The first is an empty Risc PC 2 case (unfortunately only 2 exist with prototype boards in them).
The second is the R140 which is one of Acorns Unix machines, these were very expensive and thus pretty rare.

A4000s & A5000s

My selection of A4000 and A5000 machines, some at the bottom are currently stripped down and need rebuilding.

BBCs

Here are some of the BBCs I own, I probably have the same amount again in various boxes etc.
Most of these need cleaning up, that's a job for the future including RetroBriting them all.

One major job I need to do is replace the caps in the power supplies.

Electrons

This is only about half of the Electrons I own, you can see the difference in colour between the one in the middle and the first one.
Another candidate for RetroBrite I think.

The one at the back has a Plus 1 attachment plugged in which give the machine 2 rom cartridge ports.

Master Compacts

Shown are several of the Master Compact base units I have.
The actual machines are currently stored in boxes elsewhere, need to sort them out and put them with the bases.

Network Computers

Some of the NC set top boxes that I have.
These were produced at the end of Acorns life when they changed over to doing "Network Computers" and media on demand.

Monitors

A nice selection of monitors from my Acorn monitor stash.

CUB Monitors

My horde of Microvitec CUB monitors which where the go to monitor for the BBC micro.
Every school had one of these, they are pretty much indestructible.

'

At some point I'm going to get a few more shelves from IKEA and add another row for monitors to the set of shelves below.

Parts Shelf

This currently holds various equipment such as disk drives and machines that need looking at along with items such as disk drives and keyboards etc.
There are currently 6 A7000s above this which have been dismantled so that their batteries could be removed. Some have leakage which needs to be cleaned.

The Good Stuff

Here is a view of the boxed machine section.
This is my main collection which contains boxed systems in good condition. At some point I need to photograph all of this and document what I have.

Other Stuff To Do...

There is a ton of other bits that I need to sort out but at least I can now get in and easily access the machines and shelving.

The next job is to start pulling out a machine at a time and do proper maintenance on each one.

Get other hardware that is stored in boxes and put them on the shelving, stuff like Master Compacts and various BBC cheese wedges (I have a load).

Well we are at the end of another year. This means several things, opening presents, new years resolutions to be broken and of course Retro Challenge!!

My Challenge...

This time around I'm not committing to too much. I have a week off at the start of the month so want to take as much time as possible doing the following...

Sort Out My Storage Locker

My collection of machines is no longer welcome in our house :)

It therefore lives in a secure lockup location just round the corner from our house.
Due to me moving out of my house and into my fiancées I have moved a lot of my possessions into storage. The problem is that I really need to get things like the shelving built and sort out various boxes etc to organise everything in there. I am currently having to climb over monitors to get to anything.

Update Machine List

I have started to create a list of machines that I own. I want to index all the other equipment etc so that I can decide which to do maintenance on first.
Several need looking at fairly quickly to sort issues such as leaking batteries or other problems that can't be put on hold.

Fix Machines Needing Urgent Attention

Several machines need urgent attention to stop damage to boards etc.

A while back I removed the batteries from most machines as they are the main issue in the Acorn product line. If left to leak they can eat through the board and damage machines beyond repair. A few of the machines I've been given recently are damaged beyond repair due to this problem.

Archive Machine

I bought a KryoFlux unit quite a while ago and want to use it to take archive images of my floppy disks.

I started to build a PC designed to be a standalone machine for this job. The machine has a 5.25 and 3.5 inch disk drives attached to the KryoFlux internally. I just need to finish installing an old motherboard and OS to run the software.

Backup Software

I have a pretty large collection of Acorn software, I started to backup discs a while ago and have a lot of them imaged as standard disk images. I want to use the KryoFlux unit to create archives of each disk. While doing this I intend to take high resolution images of the boxes and disk labels.

Other stuff...

If I manage to get anywhere with all of that then I will probably do some more work on my BBS software, since the Retro Challenge I have moved it to a database driven system and re-written some of the back end.
I really need to start loading pages into the system to create a usable BBS.

Using The BBC Master Compact Portable

Well RetroChallenge is over but I got chance to finally complete one of the suggestions on Twitter...

Well I put on my summer clothing and headed out to Llandudno.
Here I am playing REVS on the Beach in the blazing UK summer sun (of which there was very little).

Had to fight my way onto the beach through the hordes of Spectrum and Commodore 64 users...

More Wiring Up

Completed the various wiring bits that needed doing. Made a power board that connects the incoming power connections to the main circuits via a removable umbilical that can be removed to disassemble the machine.

Cut the circuit boards down to size with the Dremel and tied the cabling together with tape.

Glued the main power board into place.

Added in the secondary power board that provides the switching between internal power and external mains.

Connecting wires between the power boards.

VGA Output

Connected the VGA wiring harness to the internal resistors, found the ones I needed from the maintenance manual that has a full circuit diagram of the machine.

Testing the output. Works ok but there seems to be a weird problem with colours not working, the output is correct but everything on the screen seems to be white.

Power Switch

Fitted the power switch that allows me to turn on battery power.

Finished Machine

The machine pretty much completed.

Switched to battery powered mode. Screen is showing MOS command prompt.

Look no wires :)

Outstanding Bits

There are a few issues that I still need to resolve.

Firstly the VGA seems to not be displaying colour, not sure if it was just me or if there is an issue. Need to check the actual output on a real monitor to ensure that we are getting colours.

Battery needs to be fixed internally in some kind of holder so that it doesn't get hot from any chips on the board.

The original brown front has been removed, I want to get a new custom vinyl printed that will also cover the screen boarder. Didn't manage to get time to design and get it printed.

GoSDC is working ok but I'm not sure what I'm doing wrong as the patched ADFS and DFS won't seem to load.
Not getting any errors from it but the filing systems I've asked it to load don't appear. Going to try it in the normal master and see if its an issue with the Compact.

All Good Thing Must Come To An End

Well that's me done for this RetroChallenge. Looking forward to reading everyone else's blogs. See you all in the 01/Winter :)

Simulating 300bps Via Telnet

FozzTexx who runs the /r/retrobattlestations subreddit and Level 29 BBS was looking for a way to throttle telnet sessions to his BBS. He wanted to simulate the connection at 300bps.

As part of my ViewData BBS system I added in the facility to throttle the speed of the connection to give an accurate feel to way that it used to look.

Another item that is implemented is a way to pass through to an external BBS thus allowing me to either throttle or dial into telnet only ViewData BBSs.

My system was designed to handle ViewData only so I did a few adjustments and created a proxy service that will allow the connection to another BBS but will throttle the speed.

Connecting...

To connect to the Level 29 BBS with throttling enabled you can telnet (RAW) to the following ports...

Connect to - bbs.retroacorn.net

Port 6000 - 300bps
Port 7000 - 1200bps
Port 8000 - 2400bps

When I get the time I might add in a menu system to allow connection to other BBS systems.

Fixing In Place

Started by cutting down the main power board using the dremel and hot gluing it in place.

Wiring It Up

Wired up the harness to connect the VGA convertor board to the TTL RGB output of the BBC. The hooks will be connected to the resistors on the inside of the board. This means that I don't have to solder the entire lot to the board.

Just need to trim down the board using the Dremel.

Sorted out the power switch which will allow me to switch between the external power and battery.

Next job is to wire up the internal power to all of the above items.

Cutting Tracks

Had to do the bit I was not looking forward to. Cutting through the power tracks on both sides of the board.

Was a bit worried about damaging the board but was careful to remove the track with a Stanley knife without damaging anything else.

Gluing Bits In Place

Glued the power connections in place to stop then moving and protect the board.

Added in fixings for VGA convertor board.

VGA convertor board now fixed on mountings.

Soldering Power To The Main Board

After about an hour of fiddling around managed to solder the 4 wires which will take the power from the external socket to my board and back. The solder on the machine is lead and it does not want to melt. I had an absolute nightmare getting the wires through the board and getting the solder to melt on both sides. Finally after lots of fiddling got the wires soldered on.

Next tested that it actually will work from the battery. Machine initially kept powering off after a few seconds. I found the reason, i'd managed to short two of the connections on the back my perf board. Sorted that out and it works ok.

Next thing to do is cut the tracks so that the input wires are separated from the output ones, the input will power the charger and the VGA convertor board. The power from the battery board will then go back into the machine (or be powered via the input if the switch is in the correct position).