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Great Hierophant
March 21st, 2006, 07:04 PM
I have several questions about this most fascinating piece of IBM video equipment:

First, can you use standard 64x1kbit modules if you find a daughterboard with empty sockets?

Second, there are dipswitches on the EGA that allow you to set which resources it uses and what type of monitor it connects to. Does anyone give me the settings? Can the EGA truly do 720x350 monochrome output in Mode 7 when connected to a monochrome monitor or will it emulate it with Mode 1/3 640x350 monochrome?

Third, did anyone ever find a use for the two composite video ports on the card? I believe a second daughterboard would have provided some functionality , like CGA composite video support. Does such a beast exist?

modem7
May 29th, 2006, 02:18 AM
I have the IBM EGA board with its memory daughter board.
The daughter board is one third populated with Hitachi HM48416AP-15 chips in sockets U18 through U25.

As for the DIP switches:

1 2 3 4
--------
0 0 1 0 = Monochrome
0 0 0 1 = CGA
0 1 1 0 = EGA

A lot of clone EGA boards used these same switch settings.

Unable to answer your other questions.