Re: Mk14 vdu
For Tim:
This is my modified version of your Charset - it floods 0F12-0FFD and 0B00-0BFF with '@' which is a character never written by the corruption so it is easier to see when one has been replaced / overwritten.
It writes continually to 03xx in extra-extra RAM but assumes that you have the VDU set to render from 0Fxx and 0Bxx as I have found that it does stray writes to both 0fxx and 0bxx. You don't therefore see the 'char=' and the rolling character as they are being written to off-screen RAM.
I have commented out the lines which set up the 8154 ports and flags but you can easily reinstate them.
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