Hi all, Here is an adapter I've been working on to get vga output without a Second Sight card. Any techies out there want to look this over and see if it works for you. Build and use it at your own risk as I haven't tested it yet. ---------------------------------------------------------------------------= - GS RGB to VGA Video Adapter Here is a GS RGB to VGA converter adapter based on the VGA Hack for the Amiga which also uses analog RGB and works great. It will allow the use of a vga monitor on a GS. The original VGA Hack diagram can be found on Aminet (the big Amiga FTP site) under hardware hacks. The Amiga uses separate horizontal and vertical sync so I used 330 ohm= =20 resistors (as suggested by someone in the Atari ST newsgroup) and tied them together to split the composite sync. This allowed me to get a separate H and V sync to send to the various pins on the 74LS08N chip. GS Male to VGA Female converter 74LS08N chip ------- GS Male # 2 Red -----------> VGA Female # 1 |-->--->H Sync > |1 14| GS Male # 5 Green ---------> VGA Female # 2 |-->--->H Sync > |2 | GS Male # 9 Blue ----------> VGA Female # 3 | V Sync < |3 | | |--->V Sync > |4 | GS Male # 3 Comp. Sync ----> 330 ohm res -> H->| |--->V Sync > |5 | " " " " " " ----> 330 ohm res -> V---->| H Sync < |6 | ------- GS Male # 1+6+13+Shell GND ----------> VGA Female # 4+5+7+8+9+11 _|_ 100 =E6F --- | +5v from MB -------------------------> 74LS08N pin # 14 Horizontal and vertical sync outputs from chip go to the following: H Sync > VGA Female # 13 V Sync > VGA Female # 14 You will need to build this on a small PCB (printed circuit board) which is obtainable, as well as the 74LS08N chip, from Radio Shack. Note the directional arrows on the diagram above as pertaining to the 74LS08N chip. Horizontal sync goes IN via pin #1 and 2 and are joined together on the PCB and then exits to Vertical sync via pin #3. Vertical sync goes IN via pin #4 and 5 and joined together on the PCB and exits to Horizontal sync via pin #6. +5 volt goes from GS motherboard to pin #14 on 74LS08N chip. -------------------------------------------------------------------------- Disclaimer: Be warned that using this adapter is 'AT YOUR OWN RISK' as is any after-market hack. No guarantees or warranties implied or given with this diagram and instructions. Hopefully it won't blow up your GS. The final result will require plugging into a vga (male) cable. The converter will plug right into the GS. Let us know your results. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 In article , Tony Cianfaglione wrote: > Here is an adapter I've been working on to get vga output without a >Second Sight card. Any techies out there want to look this over and see >if it works for you. Build and use it at your own risk as I haven't >tested it yet. This circuit does nothing for the refresh rate, which is outside the range of most modern VGA monitors (some older models, like the NEC MultiSync 3D I use, can handle the GS's 15.75 kHz horizontal sync rate.) What could be more useful would be this sync doubler: http://www.aminet.net/~aminet/dirs/aminet/hard/hack/Syncdoubler.lha A conversion of this archive to something readable by a wider variety of computers is on my website: http://salfter.dyndns.org/files/Syncdoubler.zip I haven't tried building this gadget yet, but it looks like it would double the horizontal scan rate. It also looks at first glance, though, like it would only display half of each scan line...unless I'm reading something incorrectly. It uses a 74LS123, three 2N2222s, and a few passive components and could be lashed together quickly enough to see if it'll get the job done. _/_ / v \ (IIGS( Scott Alfter (remove Voyager's hull number for email address) \_^_/ http://salfter.dyndns.org -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE7Ai6ZVgTKos01OwkRAsePAKC4a/zHgLWIH6kQiaU/SEpLj1bcRACdG0JW VbZrq2Q6efqqUAQbRk8UlcU= =7vjn -----END PGP SIGNATURE-----