This is my first post in this forum so I want to say Hi to everyone and I hope to learn and share my experiences with all of you
I opened this thread because I want to modify some behavior to my Ati X550 Pci-e videocard.
I want to edit the bios to force the card to work with an Horizontal Refresh (VGA Monitor) of 31KHz.
I'm not crazy (not yet ), but this mod is necessary for to force the videocard to work correctly with the Arcade monitors (the old 80-90's game cabinets, like street fighter 2, metal slug etc).
There is a guy on internet that sell a video card (derivated from X550 Ati card) that does what I want to do!
This is the link: http://www.ultimarc.com/avgainst.html
In the page above is shown the picture of the ArcadVga 3000, but the "old" ArcadVga2 was exactly an X550 video card!
In the section "TheArcadeVGA card has the following built-in resolutions:" of the link above are listed all the resolutions available.
On internet is possible to download the bios of this card but there is a sort of protection to
avoid cloning (in fact the first version of the ArcadVga1 was reversed!).
So what I want to do is "simple", I want to know if I can change from the original BIOS of my videocard the LUT where all resolutions are stored.
I disassambled the code of a X550 Bios (downloaded from this site) with IDA (obviously in 16bit) and I started to reverse from searching all int 10h interrupts to reach to find the procedure of set video mode, but I'm not be able to continue because I didn't find usefully code!
N.B.
In the ArcadVga bios there are three "int 10h" instead of two available in all X550 bios that I saw.
Somebody with skills of reversing bios video could help me?
Thanks a lot.
Here it is possible to find the bios that I'm using: http://depositfiles.com/files/gys82xl13
Bye
I opened this thread because I want to modify some behavior to my Ati X550 Pci-e videocard.
I want to edit the bios to force the card to work with an Horizontal Refresh (VGA Monitor) of 31KHz.
I'm not crazy (not yet ), but this mod is necessary for to force the videocard to work correctly with the Arcade monitors (the old 80-90's game cabinets, like street fighter 2, metal slug etc).
There is a guy on internet that sell a video card (derivated from X550 Ati card) that does what I want to do!
This is the link: http://www.ultimarc.com/avgainst.html
In the page above is shown the picture of the ArcadVga 3000, but the "old" ArcadVga2 was exactly an X550 video card!
In the section "TheArcadeVGA card has the following built-in resolutions:" of the link above are listed all the resolutions available.
On internet is possible to download the bios of this card but there is a sort of protection to
avoid cloning (in fact the first version of the ArcadVga1 was reversed!).
So what I want to do is "simple", I want to know if I can change from the original BIOS of my videocard the LUT where all resolutions are stored.
I disassambled the code of a X550 Bios (downloaded from this site) with IDA (obviously in 16bit) and I started to reverse from searching all int 10h interrupts to reach to find the procedure of set video mode, but I'm not be able to continue because I didn't find usefully code!
N.B.
In the ArcadVga bios there are three "int 10h" instead of two available in all X550 bios that I saw.
Somebody with skills of reversing bios video could help me?
Thanks a lot.
Here it is possible to find the bios that I'm using: http://depositfiles.com/files/gys82xl13
Bye