Markco wrote:
This card is digital RGB. Composite 80col video will be output the normal way (the connector from the motherboard, and will be no better than with a standard 80col card).Hi all; I am having difficulty getting RGB output from the 80 column extended RBG card in an apple IIe. I get a black screen when a standard RGB monitor is connected. The connector is putting out composite signal, that I am sure of.Trying different monitors, I found one that has the skewed composite output. Output is normal on the composite connector, both in 40 and 80 column mode. Is there a control, or escape sequence that will switch the output to RGB? I have no documentation. Thanks ahead of time
The correct monitor to use is the AppleColor M100 which has matching digital inputs.
An analog monitor can't be used directly. There needs to be what Apple calls a summing network.
The 4 digital signals make out the codes of the colors. The signals arent even the components because the Apple colors aren't made by just mixing two levels of R, G and B.
Getting this monitor or similar seems almost impossible, those who have them hold on to them, especially here in Europe. So to use my card I made an interface for a CGA monitor. You can also find (on the net) a description of how to make an interface for an analog RGB monitor like the IIgs monitor.
http://home.online.no/~kr-lund/A2E-CGA.htmThe trick was to break composite sync into separate HSync and Vsync. I also created a GAL that would swap the CGA colors around a bit so they match the Apple colors better (not documented yet). Using the CGA has been very nice.
In my page you will also see the pinout of the RGB card... Knut