Hi.
After 14 years, I thought it was time I gave the Micro UK101 a re-visit and a refresh.
I have updated the circuit slightly to make the chip selects based purely on address lines, and OE and WR more conventional, using Phi2 and the R/W. The E select on the 6850 is also now utilised, so follows "conventional" connections.

Also added the memory map to allow you to see the reasoning behind the decode logic.

I have also taken on board all comments in this forum, and updated the MAX232 and clock generator circuits with what you have said - I DO listen

The layouts and circuit has been re-visited and quite a bit of work done to improve the images - they are also now in colour (I can use Visio better than I could 14 years ago!).



The URL of the page is unchanged...

http://home.micros.users.btopenworld.com/uk101/uk101.html

Please refresh the page in your browser to make sure you see the latest version - it will show last update of 18th January 2012 near the top.

Regards.

Grant

Great work!

Nice one, Grant!

Thanks for your comments. I will be updating my board with the changes to make sure it works, but if anyone can spot any errors with what I have done, please feel free to let me know.

Regards.

Grant

Hi.

I am pleased to say that the Micro UK101 page has now been "officially" re-launched

I have done further updates to all diagrams (hope you like them).

I have also changed the clock to use a 4MHz crystal instead of 8MHz, and the first divider is replaced with a cheaper / common 74LS74.

To make sure the information that I have provided is correct, I have totally re-built the Micro UK101 using only the information that I have published (following the wiring diagrams exactly) and it worked first time.

http://home.micros.users.btopenworld.com/uk101/uk101.html

Please refresh your browser to make sure you can see the new page and diagrams (will show "Last update: 22nd January 2012" near the top).


Regards.

Grant.

http://home.micros.users.btopenworld.com

That's a real nice collection of computers you've got there!