Really BIG Letters & Numbers

Publison

Here are some results I got from two NTSC monitors in my Propeller Lab.

The first two screen shots are from 20" Toshiba Multimedia TV (1995) MM20E45 (TIMM)






The second two screen shots are from Timothy's 3" LCD (NSTC) Monitor:

http://www.brilldea.com/product_30LCDanddriver.html








I get considerably good outputs from both of these monitors. Some slight artifacts show up, but not the the extent that you have.

I wonder how the Parallax monitor differs?

Perry

"tv_text" and "tv_terminal" drivers are fundamently different.

"tv_text" uses the ROM font for characters (program 872 longs, variable 150 longs)
"tv_terminal" uses vector graphics to produce characters. (program 1231 longs ,variable 860 longs

It appears that the "tv_text" driver actually produces clearer characters.
If you have no use for the graphics functions the "tv_text" driver would be the better choice.

Humanoido

Publison, thanks for showing the photos from the two monitors. They have excellent results. The 20-inch Japanese Toshiba I would expect to have sharp images. Timothy's 3" LCD (NSTC) Monitor is excellent too. The artifacts are very minimal. This gives a good example of the performance of other brand TVs.

Humanoido

Perry wrote: »

I suspect it has something to do with interlace. My display is a B/W tv, don't have an LCD. Parallax does not seem to supply that little 3.5 inch any more. Need to know the exact horz/vert pixels. Try changing

  y_spacing = 12        '13 = normal

near the top of tvBIGterminal.spin

Thanks Perry. Wow! That change completely cleared up the bottom of all the characters, which is a substantial improvement overall. However, it introduced artifacts just under the top of the character. Changing the color from green to white did not make any change in the artifacts. The small discontinued Parallax monitor is 320 x 240 pixels.

potatohead

It appears that little TV does not handle interlaced signals well.

Humanoido

Potatohead: it definitely does not like interlaced - Andy's mod with the text in ROM driver is rock solid, so I think graphics can stay with the interlaced graphics driver and text can stay with the text in ROM text driver. I also noticed the first interlaced line looks good, second line is ok, but third line and after has artifacts. Lower case is more difficult. However, the change suggested by Perry is an improvement - it makes the upper case characters more readable. It's going to be a compromise with the graphics. Probably the ace with a graphics driver is the color capability. The input given in this thread has helped to have the best solutions for my project, understand what's happening, and offers solutions for setting characters, rows and columns. Thanks to all! I am very grateful.