Vs. Gradius Free Play Attract Mode Hack

davesies

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Inspired by Matt Osborn and others' work on SMB1/Excitebike, I decided I wanted to make a hack for my Vs. Gradius which would allow the attract mode to work during free play. I've hacked something together which works in Mesen, but I am hoping to find some beta testers who have both: (1) a Vs. Gradius board and (2) a ROM burner so they can burn a custom ROM of the game.

I don't have a burner so I unfortunately have no way to test on real hardware, but I'm hoping I can find some help here.

Send a DM if you're interested. This isn't a high score save hack, just adds freeplay attract mode. For now the hack pretty much assumes you're gonna keep your cabinet in free play mode, so other dip settings will cease to work. I could probably improve it a bit to make it mostly function with normal dip settings, though the "insert coin" text has been replaced with "free play" which will affect all modes.

Hope some people find this useful. As a recent red tent acquirer, I've been obsessing over it and I'd love to get all my games to work with attract mode + freeplay, so the cabinet looks more interesting while its powered on and also to avoid burn-in on the monitors. Once I'm finished with Gradius I plan to move to Dr. Mario, then hopefully Tennis and Balloon Fight (though I'm not sure how much extra effort the dual screen games will be, I'm curious to find out...).
 
Inspired by Matt Osborn and others' work on SMB1/Excitebike, I decided I wanted to make a hack for my Vs. Gradius which would allow the attract mode to work during free play. I've hacked something together which works in Mesen, but I am hoping to find some beta testers who have both: (1) a Vs. Gradius board and (2) a ROM burner so they can burn a custom ROM of the game.

I don't have a burner so I unfortunately have no way to test on real hardware, but I'm hoping I can find some help here.

Send a DM if you're interested. This isn't a high score save hack, just adds freeplay attract mode. For now the hack pretty much assumes you're gonna keep your cabinet in free play mode, so other dip settings will cease to work. I could probably improve it a bit to make it mostly function with normal dip settings, though the "insert coin" text has been replaced with "free play" which will affect all modes.

Hope some people find this useful. As a recent red tent acquirer, I've been obsessing over it and I'd love to get all my games to work with attract mode + freeplay, so the cabinet looks more interesting while its powered on and also to avoid burn-in on the monitors. Once I'm finished with Gradius I plan to move to Dr. Mario, then hopefully Tennis and Balloon Fight (though I'm not sure how much extra effort the dual screen games will be, I'm curious to find out...).
Too bad I don't have a Gradius or Goonies or else I'd help out. I can't wait for new developments though, I always love these kind of mods.
 
I broke down and ordered an EPROM programmer from Amazon so I'm gonna do some testing on my own cabinet soon, whenever I can get my hands on some chips. Will reply once I've had a chance to thoroughly test on my cabinet and then will release to the community for anyone else with a red tent and a Gradius board.
 
Update: I broke down and bought an EPROM programmer and tested my hack this morning, and it works great!

Here are some demos of it in action. I will note that this hack does not attempt to play nice with other dip switch settings, so its intended for folks who want to keep their machine on free play. The other thing I haven't yet reverse engineered is the checksum mechanism that the game uses. So when you boot it will say ROM 1 is out, but the game still boots just fine.



Anyone who wants to install this hack, please watch this space. I am gonna put the bin file up on github real soon for anyone who wants to burn their own copy. Hope this helps the handful of red tent owners who enjoy Gradius and like to have attract mode enabled during freeplay.

Next up on my TODO list is Vs. Dr. Mario, so hopefully I'll have some progress to share on that before too long!
 
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