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Motorola 6847: Difference between revisions

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Redirected page to Video Display Generator
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#REDIRECT [[Video Display Generator]]
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The MC6847 is a video display generator chip that is designed for the 6800 family of microprocessors.  It reads data from memory (via the [[SAM]] chip) and displays the contents on screen.  The 6847 is used on Coco 1 and 2's only; this function was replaced by the custom [[GIME]] chip in Coco 3 models.
 
The chip provides a 32×16 alphanumeric display, or graphic displays up to 256×192 pixels in resolution.  Additionally, a variety of "semigraphics" modes are provided.
 
On the Coco, the familiar dark-green on light-green text is generated as a fundamental function of this chip.
 
In Coco 1's and most Coco 2's, the 6847 is not capable of displaying lowercase.  Instead, lower case text appears inverted. Later Coco 2's replaced the 6847 with a 6847T1 that can display proper lower case text.
 
==See Also==
*[[VDG]]
*[[Video Display Generator]]
*Wikipedia article on the [http://en.wikipedia.org/wiki/Motorola_6847 Motorola 6847]
*Datasheet http://instruct1.cit.cornell.edu/courses/ee476/ideas/mc6847.pdf
 
[[Category:Hardware]]

Latest revision as of 15:58, 14 April 2026