Keeping Ceefax alive with NMS Ceefax | The MagPi #118

The BBC closed its Ceefax service in 2012 but Nathan Dane is keeping memories of the iconic blocky service alive. In the latest issue of The MagPi, out today, David Crookes takes a look.

Before the internet, there was teletext – a brightly coloured, blocky-looking information service built into a huge number of television sets from the mid-1970s onwards. It allowed millions of people to read news and sport headlines, check the weather, find travel information, view TV and radio listings, and even play a quiz or two.

NMS ceefax homescreen
You can view the pages on Nathan’s website using an interactive viewer created by Alistair Cree

But while it still exists across the world, many popular services have long been axed – including BBC Ceefax which ended in 2012. Rather than allow its memory to wither, however, enthusiasts are determined to keep this charming service alive, among them Nathan Dane who had recreated his own version of Ceefax on a Raspberry Pi connected to a VBIT-Pi board.

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Nathan’s original aim was to produce a teletext service as a personal project. “I only really wanted a service that would be useful to me and my family, so I coded things like the national and local news headlines for my dad to read, and wrote ‘school news’ and other information for my sister and I,” he explains.

Original ceefax screen
This fuzzy image shows how the teletext signal looks in the Vertical Blanking Interval (VBI). “This was made visible by adjusting the V-Hold on a CRT to ‘roll’ the VBI down into view,” Nathan says

To do this, he made use of Peter Kwan’s VBIT‑Pi project and Alistair Buxton’s Raspi-teletext software. “The VBIT-Pi adds the teletext signal to any PAL composite video signal so you can play a TV channel through it and add teletext,” he says. “Raspi-teletext adds the teletext signal to Raspberry Pi’s composite video output, and anyone can use it to generate teletext without additional hardware.”

At first, he would manually type stories from BBC News – which he found too time-consuming, despite the 40-column text screen limitations. It was then that he started scraping the BBC website for news and sport content, going as far as adding the ever-popular football league tables.

Raspberry Pi can generate a valid teletext signal without VBIT-Pi, but the board allows teletext to be added to an existing video signal

“The BBC offers RSS feeds – XML documents automatically filled with links to the latest headlines,” Nathan says. “My code parses these links and extracts the text from each page. One issue, of course, is that some stories don’t fit well into the teletext format, such as reports made up mostly of photos or videos, so I had to build in checks to remove those.”

Rain or shine

Nathan also tweaked the Ceefax page design so that it would allow headlines longer than 35 characters and he made his NMS Ceefax, as he calls it, draw data from other sources, too. TV listings, for instance, come directly off-air from the Freeview Electronic Programme Guide. Weather, meanwhile, is taken from the Met Office’s API – a decision that overcame a major challenge.

“For those who don’t remember, the Ceefax weather map was essentially a blocky outline of the UK with areas shaded in different colours,” Nathan explains. “Coloured text around the edges told of the weather to be expected in the corresponding area, but this was challenging to recreate because it relies on a lot of ‘fuzzy logic’.”

Nathan has designed his own VBIT-Pi 3 board which adds a teletext stream to a PAL video signal

At first, he hard-coded the four UK countries in different colours and included the data beside each of them. By taking weather from the Met Office, however, Nathan could download weather data for the UK’s eleven regions. “Comparison code then grouped all the areas with similar conditions under one colour – it’s not perfect, but it’s close enough to do the job,” Nathan reveals.

Having kept the project for personal use for a long time, he’s now made his Ceefax publicly available online, where it’s gone down well with visitors. “I was initially drawn to teletext because it was an old broadcast technology that I could recreate, but I very quickly came to love the simplicity of the format,” he says. “People have said hard limits induce creativity and this couldn’t be more true with teletext.”

Get The MagPi #118 NOW!

You can grab the brand-new issue right now from Tesco, Sainsbury’s, Asda, WHSmith, and other newsagents, including the Raspberry Pi Store in Cambridge. You can also get it via our app on Android or iOS. And there’s a free PDF you can download too.

MagPi 118

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2 comments
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301 Sports, 302 Football index. Still in my remote controller muscle memory.

Reply to Anders

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In Norway it is still active both over the air and as a web service. https://www.nrk.no/tekst-tv/190
NRK is the Norwegian equivalent to BBC.

Reply to Bjarte

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