I thought I would give an update on this project.
With lots of help from Boffin1 (Thanks John), and using his display board, I now have a working countdown timer. XD
Here is a link to a short video on Youtube:
sorry it's a bit dark but the video really didn't like the brightness of the displays.
and a couple of pictures:
The only issue I currently have is the accuracy. I have been playing but can't seem to get it very accurate. The best I have managed, so far, is losing 5 secs per 10 mins which is horrendous! I need to keep playing with the code to see what I can do.
So a big thanks to Crossraods and Boffin1 for getting me this far.
I will do another update, maybe for help on improving the accuracy, but definitely when I have it boxed and ready.
Dave