MediaWiki:Sitenotice:
2024-03-02: The wiki ran out of disk space, so things were not working. This has been resolved by adding another 5GB of quota ;-) Thanks to Tim Lindner for reporting the issues. 2020-05-17: If a page gives you an error about some revision not being found, just EDIT the page and the old page should appear in the editor. If it does, just SAVE that and the page should be restored. OS-9 Al (talk) 12:22, 17 May 2020 (CDT)

Motorola 6847

From CoCopedia - The Tandy/Radio Shack Color Computer Wiki
Revision as of 06:43, 28 September 2014 by Mmaydaniuk (talk | contribs) (Created page with "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 conten...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

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 32x16 alphanumeric display, or graphic displays up to 256x192 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.