[Coco] Preventing cursor blink at very high clock speeds on a Coco

[Robert Gault]

I've become aware that some people are running Coco emulation at very high clock speeds. This is 
easy with VCC and MESS. It may also be possible with new hardware such as the CocoFPGA.

Well at 18+ MHz the cursor blinking is giving some people fits. :) Here is a way to turn off cursor 
blinking with a Coco3.

Write and LOADM the following:
	org	$f77e
	fcb	$21	brn	prevent blinking in Width 40 & 80 modes
	
	org	$a1a5
	fdb	$1212	nop	prevent blinking in Width 32 mode

	end

With a Coco 1 or 2, you will need to change your ROM as these don't run in all RAM mode. All version 
of the Basic ROM can be altered at $A1A5-$A1A6 by changing the $8B10 to $1212.

Robert