[net.micro.cbm] VIC-20 graphics

davec@tektronix.UUCP (Dave Clemans) (09/22/83)

Does anyone know how to get graphics out of a VIC-20 without buying CBM's Super
Expander Cartridge???  I can't quite figure out how it's done...  The Super
Expander has a resolution of 160x160 pixels.  Each character cell is 8x8, which
would require 20x20, or 400, unique characters when only 256 are possible with
8 bit data.  The Video Chip (a 6560, I think) has a 12 bit data bus, the upper
four used for color.  Are these possibly being used to increase the character
addressing to 9 bits???
If anyone knows the answer, I would appreciate hearing from you via mail.

							Thanx,

							Greg Muth

							   aka

   						    tektronix!gregorym

burke@ittral.UUCP (Michael G. Burke) (09/23/83)

The superexpander uses the vic chip in a mode where each character
is defined by a 16 by 8 array, i.e the screen is actually showing
10 lines of 20 double height characters.  See the programmers reference
guide for furthur info.

gregorym@tektronix.UUCP (Gregory Muth) (09/29/83)

I don't know why my article asking about VIC-20 graphics has someone elses
path name???

If you reply to the article, please send mail to "tektronix!gregorym"

thanx,
greg muth