New interview with Jotego on the Technical Development and Secrets of the Neo Geo AES+

The interview takes place at the Retrópolis event in Valencia, Spain. Jotego, a renowned figure in the FPGA (Field Programmable Gate Array) scene, is revealed to have officially participated in the development of the Neo Geo AES+ by SNK/Plaion.

• Professional History: Jotego studied Telecommunications Engineering in Valencia. He worked as a microelectronics engineer for Analog Devices in Ireland and spent four years at Texas Instruments in Japan.
• Rise in the Scene: He returned to Valencia and began working on emulation projects. His breakthrough occurred when a YouTuber featured his work on FPGA (MiSTer), leading him to create over 70 arcade cores supporting more than 1,000 games, funded via Patreon.

The Genesis of the Neo Geo AES+ Collaboration

• The Contact: Plaion contacted Jotego because they wanted to use his Intellectual Property (IP) honestly under the GPL3 license.
• The Team: Jotego worked alongside Furrtek, a French engineer famous for reverse-engineering Neo Geo chips. While SNK provided the brand license and quality control, they no longer have the original engineers from the 90s; therefore, they relied on scene experts like Jotego and Furrtek to build the machine.

Hardware Comparison: AES+ vs. Original

• Reliability: Jotego asserts the AES+ is "better" because it is brand-new hardware. Original Neo Geos are aging, with failing capacitors.
• Efficiency: The new chips are manufactured in Europe. They consume less power and generate significantly less heat, which extends the life of the components.
• A "Model 2" Revision: He classifies this not as a mere replica, but as a Neo Geo Model 2. The original motherboard had six to eight main chips; the AES+ condenses these into just two modern chips while keeping the exact same logic.

Audio and Video Fidelity

• Video (Native RGB & HDMI): Unlike the MiSTer, which uses a generic video converter, the AES+ uses the original analog DAC (Digital-to-Analog Converter) circuit design. This ensures that the RGB output displays colors exactly as they appeared on the original console.
• The "Aliasing" Secret: In his MiSTer cores, Jotego usually adds an "interpolator" to smooth the sound. However, for the AES+, they removed it to preserve the original hardware's "aliasing" (digital noise/artifacts), which provides the specific audio "crunch" fans expect.
• Audio Components: The sound system perfectly replicates both the FM synthesis (similar to Mega Drive/Genesis) and the two distinct PCM (digital) channels used for high-quality samples and compressed voice.

Latency and Input Lag

• Zero Lag: Jotego confirms there is zero input lag. On a MiSTer or PC, signals go through USB polling (even at 1000Hz). In the AES+, the controller cable is hardwired directly to the logic chip. The moment the processor checks the button state, it sees the physical signal immediately, matching the original hardware's performance.

The Cartridges and Future Projects

• Cartridge Costs: The 80€ price tag is due to the use of Flash memory chips. Unlike the 90s, where massive quantities allowed for cheap "Mask ROMs," current production runs are smaller, requiring expensive Flash chips.
• The Future: Jotego hints that Plaion is looking at other systems. He specifically mentions the Sega Mega Drive as a perfect candidate for this type of hardware replication because the technical documentation is already complete (Could it be a Neo Geo Pocket?).

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Link to the full interview:

https://www.youtube.com/watch?v=rgHGL5TSR-s