Jotego's new FPGA core brings Twin Hawk and Superman to MiSTer

FPGA developer Jotego has released a new core for the Taito X arcade system, bringing five late-80s coin-op titles to modern hardware. The update is live on Jotego's Patreon and adds support for Superman, Twin Hawk, and three other arcade boards.

The Taito X hardware shares a lot of architecture with Jotego's existing JTKIWI core, which handles games like The New Zealand Story. It's also the first JT core to use a Yamaha YM2610 sound chip. That's the exact same audio hardware found in the Neo Geo. Despite the massive popularity of SNK's console, the YM2610 rarely showed up in other arcade platforms.

The Taito X lineup

Five games run on this specific hardware. Taito developed Superman in-house in 1988. It's a side-scrolling action game where the Man of Steel has a massive hitbox and a goofy mid-air kick. I'm not entirely sure why Superman needs to physically kick people while hovering, but it makes for a funny arcade experience.

Toaplan handled Twin Hawk, a 1989 vertical shooter. You pilot a fighter jet, but every single enemy in the game is a ground-based tank. Because the tanks follow roads, their movements are somewhat predictable, but they can also reverse direction. The game doesn't use a traditional screen-clearing bomb. Instead, a helper button summons a formation of six support craft from the bottom of the screen to lay down continuous fire.

East Technology developed the remaining three games. Gigandes is a side-scrolling shooter that lets you swap between 11 different weapon types. I think Gradius already pushes the limit on weapon management, so 11 feels slightly absurd. When you die, you'll respawn immediately with your gear intact. Clearing a stage resets your weapons back to the default single shot.

Balloon Brothers is essentially upside-down Tetris. You match colored balloons, and rotating the pieces cycles their colors from green to red to blue. Last Striker rounds out the list. It's a fast-paced, 4-on-4 indoor soccer game with anime-styled characters and matches that end in under a minute.

Hardware level fixes

Jotego also pushed several bug fixes across the broader core library. The update repairs missing letters in Gradius III, fixes a background layer offset crash in Street Fighter III: 3rd Strike, and resolves circular analog stick inputs on CPS3 hardware. OutRun received more robust PCM audio code, which paves the way for a future Space Harrier core.

The 1943 core received a fundamental change to its protection logic. Jotego removed the software emulation of the protection system entirely. He replaced it with the real MCU circuit logic based on a newly available ROM dump for the intel i8751 module. The gameplay hasn't changed at all. It just means the core now uses the original circuitry instead of a software workaround.