Re: 80 column extended rgb card problem

["Bryan Parkoff" <none@nospam.net>]

"Knut Roll-Lund" <kr-lund@nogarbage.online.no> wrote in message 
T42dnWwI0O1_cGHe4p2dnA@telenor.com">news:T42dnWwI0O1_cGHe4p2dnA@telenor.com...
> Markco wrote:
>> 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
>>
>>
> 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).
>
> 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.htm
> The 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
Everyone,

    I thanked Knut for making two adapter cables.  First adapter cable is to 
convert from Apple //e's RGB / 80 column card to CGA monitor through LM1881 
chp.  LM1881 chip separates composition into H sync and V sync.  Second 
adapter cable is only an additional cable to swap CGA color to match almost 
Apple //e's 16 colors through GAL chip.
    I am satisfied to use two adapter cables, but I do not satisfy with CGA 
colors (not same as Apple II's 16 colors) so I have to accept what I have 
now.  It has three options to swap colors on color 9 and color 14 to select 
CGA bright magenta, bright red, and cyan.
    I recommend you to use CGA digital monitor using one or two adapter 
cables what you satisfy to accept it.  I have been using it almost everyday 
and it is working excellent.
    I ask Rudy or someone to add the information to the Apple II FAQ monitor 
category.  Good job for Knut.  :)

Bryan Parkoff