View Full Version : ATI EGA Wonder / Composite video

September 12th, 2010, 10:09 PM
I Have an ATI EGA Wonder video card in my IBM 5155 Portable. This card does a great job when driving the internal amber monitor, however, when I connect my flat panel TV to the composite output, I get black and white only. (when I did this with my original CGA card I was able to get low res color) I assume that the color burst signal is not getting thru or is disabled for some reason. The specs for the ATI Small wonder mention an option to disable the color-burst signal on the composite output, but I can find no info for this on the EGA Wonder. Can anyone shed some light on this?

P.S. According to the specs for the 5155's internal monitor, it blanks the color burst signal that is generated by the CGA Adapter. I would not think that would affect the external composite connector of the EGA Wonder? Any ideas?

September 14th, 2010, 03:53 PM
Try disconnecting the internal monitor and see what happens, that will tell you for sure.

September 15th, 2010, 06:42 AM
The EGA Wonder's manual states that with a composite monitor color is "converted to shades" in CGA and EGA modes (64 shades interlaced for EGA)

September 15th, 2010, 08:50 AM
The Small-Wonder*/EGA-Wonder**/VGA-Wonder has their own unique way of handeling the conversion of the different video modes to different monitors.

The EGA-Wonder** uses a chip from Chips technologies (problably) for EGA, along with an ATI16899-0 chip (problably for MDA/CGA emulation, monitor conversion and other misc. things). Those cards were also partally VGA-compatible.
The Small Wonder* uses the ATI18700 chipset, and it has hands-down the best compability with the older pre-EGA standards. The only thing it don't support as of I know is the dreaded "CGA-Snow".
The VGA-Wonder uses the ATI18800-x/ATI28800-x chipset, which sacrifices some compability*** (plantronics mode/Single-page Hercules mode/composite output) and adds full and extended VGA support. This chipset don't convert VGA to the digital monitors, but it converts pre-VGA modes to analog monitors. It's the first ATI series of cards to not have an actual crystall that is a multiplication of the MDA pixel-clock.

* Better known as the "Single-chip" versions of the Graphics Solution.
** Not including the EGA wonder 800+, as this card is just a stripped-down VGA-EDGE (which is of the VGA-Wonder family).
*** Compared to the Small-Wonder.