In article , "Arkain" wrote: > I seem to remember that the Apple file://e enhanced, at least the one I > had(it died 8 years ago), had an undocumented video mode that can only be > described as 40 column color text mode. To enable it I would: > > ]PR#3 > ]POKE 49164,0 > ]POKE 49246,0 > > **Note I may be about the addresses, but I'm certain that the 80 column > firmware had to be on, the system had to be in 40 column text mode, and that > AN3 had to be off. ** > > This seemed to set up a 40 column text mode that used the high nibble from > the Ext 80 card for the foreground color and the low nibble for the > backgound color. I want to know if this peculiar text mode can be reproduced > on any other system out there with an (Extended)80 column card, or was this > just a lucky glitch in my system... Interesting. I tried this by doing a PR#3, pressing ESC-4, and typing in the POKEs you mentioned above, and I could not produce this mode using my IIgs. I went into the monitor and stored some random data in the video page in bank 01, but still could see no change. It probably was just a lucky glitch. In case I'm missing anything, can you remember exactly what you did that caused your IIe to enter this mode? Wait just a sec. I'm going to see if this happens in my Apple IIe emulator... Nope. Can't produce it in that, either. It doesn't seem like there should be a mode like this, because the IIe only uses "digital" chroma output (hence the six hi-res colors, white, black, blue, orange, green, and magenta), I think. Let me take just a second to explain my theory. The chroma is actually two signals, interlaced together. Each signal is an axis on a square, like this: +--------------------+ | | | | | | | | Y Axis | | | | | | | | | | | | +--------------------+ X Axis The X axis varies between magenta and green, and the Y axis varies between orange and blue (like Lab color), like this: Orange +--------------------+ | | | | | | | | Y Axis | | | | | | | | | | | | Blue +--------------------+ Magenta X Axis Green And in the middle of each axis is white. Here is where some colors fit in: +--------------------+ |Red Orange Yellow| | | | | | | Y Axis |Magenta White Green| | | | | | | | | |Purple Blue Cyan| +--------------------+ X Axis Now my theory is that the Apple II only uses the extreme edges of each axis, and only one axis at a time, so we can only get: X Axis Y Axis White Center Center Orange Center TopExt Blue Center BtmExt Magenta LftExt Center Green RgtExt Center Now, lo-res graphics (and double hi-res graphics) are simply made up of tiny pixels of the same colors, so they just look like more colors. You can see this on a greenscreen monitor: all of the hi-res pixels look white, but the lo-res blocks are made up of various patterns of white dots. And since the pixels that make up the text characters are too small, we can't make 16 colors with them. This was all done just to make the hardware simpler. The only Apple II to break this theory is the IIgs, but then again, that has a whole different video display system altogether. Just so you know, I have sources on that X-Y axis thing. Check the NTSC web site. -- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ jonrelay@napanet.net ICQ# 76731065 kellys.home.dyndns.org Don't forget: Tammy Day on February 15th! Please change '.com' to '.cjb.net' to respond.