Thread: Mk14 vdu
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Old 30th Jun 2020, 11:17 pm   #99
Timbucus
Octode
 
Join Date: Mar 2019
Location: Barry, Vale of Glamorgan, Wales, UK.
Posts: 1,364
Default Re: Mk14 vdu

That has been an interesting diversion for an hour - I struggled to work out what was happening - especially as I had not looked at your code and when I did to remove the auto run realised it did not have code to enable my VDU... just a comment where to put it... so how the hell did it work on auto-execute to display the picture when I ran it first time?

Well luckily the corruption which puts 0880 in the last two bytes means that the Status Register on GO allows Flag 2 to be reset for me. If the last byte of the image is changed to 0x84 (from 0x86) I can manually run it and the only corruption is that one bit not the entire end of that line...

I spent ages looking for a final Reset in send14 as the only way I could see how the VDU got re-enabled! I did take a quick look if I could spot why it happens but, my eyes are now bleary...
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