Mkb@CMU-CS-C.ARPA (11/02/83)
From: Mike Blackwell <Mkb@CMU-CS-C.ARPA> I remember reading a blurb in some magazine (probably Electronics) about a month or two ago about a chip, but of course now I can't find the blurb, and the details I remember are a little sketchy... Does anybody know what chip I'm thinking about? As I remember, the chip was made to be interfaced to a microprocesor, and took care of all the overhead of generating color vectors on a color raster display. I believe that it also did things like scaling. I'm pretty sure that this chip was produced by NEC... Does this ring any bells? All help will be much appreciated! cheers, -m-
kevinw%isl@BRL.ARPA (11/04/83)
the only chip i know is the m7220 which is a graphics chip which may be used
in parallel to provide grey/color processing. each chip can handle 4
bits at a time i believe so you could get 8 color + intensity or so on
one chip or 16 levels of gray. if you used 3 of them that sounds like
a purty good like chip. anyway, it draws vectors, arcs, and has the hooks
for zoom and pan. it will handle ~1k by 1k and even sortof characters. it
also has 2 windows i believe for scroling/zooming, there is a reasonably
good application note from nec. intel is also making it, along with
a high powered (for intel) text processing display chip...
cheers,
-- Kevinss@rabbit.UUCP (11/04/83)
The chip you are thinking about is the NEC uPD7220 (mu P D). It is a Graphics Display Controller with some pretty features. It takes care of the video display memory. Among other things it has : DMA transfers between system and display memory via 8257 or 8237 type DMA controllers : Light pen input : Graphics and character modes (mixed or independent) : Independently scrollable areas on the screen : Line,arc,circles,rectangle drawing capability : Zoom and pan functions for graphics They have an extensive Design manual for the chip. It was described in more detail in the April 7,1981 issue of ELECTRONICS. You can get more information from NEC Electronics U.S.A. Inc. Microcomputer Division One Natick Executive Park Natick, MA 01760 (617) 655-8833 Sharad Singhal