Andy Rea wrote:i think it would be prudent to use an FPGA, or maybe a microcontroller ( avr , pic, propeller, ect ) with much faster clock rates that shod allow one to create any arbitrary waveform with the appropriate bitstream to create a teletext page.
I'm sure at least one (maybe more) micro-controller projects already exist. Sorry, I don't have a link.
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer being good this year.
dr beep wrote:How often could you 'refresh' the content of the page.
If frequently you can indeed use the settings of teletext as a screen and resolution.
(when it works the emulators must get add a TELETEXT screen)
As far as I know one page is transferred per frame in the top margin lines.
So about 50 pages per second, the TVs do it in a round robin manner but you could also decide to update only one single page (100 for example) or (as many stations do) update 100 every one or two seconds to get a faster picture while transferring the rest in other frames. I am a big fan of teletext and very important is to have a TV which can store 1000 pages or so. I hate waiting for a page to be transferred in memory page by page. This can take up to 10 seconds when changing pages without sufficient teletext memory.
"The Earth is just too small and fragile a basket for the human race to keep all its eggs in." ― Robert Anson Heinlein
Elektronika MK61, Psion series 5mx have now. Many years ago had Spectrum 48, 128k/TRDOS and Amiga A600 ...
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer being good this year.