I had the pleasure of picking the brains of David Shadoff, who is a developer and preserver of many things Retro and FPGA Gaming related. Below are just some of the key points that were covered. To get the full conversation please see the embedded video at he bottom of the page.
Introduction to David Shadoff
00:00:22 David Shadoff is a significant figure in the retro gaming and preservation community, focusing on both the software and FPGA aspects of the PC Engine and PC-FX.
00:00:52 He started programming in the 1970s and began reverse engineering the PC Engine in 1989.
00:01:29 For the past five to six years, he has been a key contributor to the MiSTer project.
PC Engine and the MiSTer Project
00:02:27 David was initially drawn to the TurboGrafx-16 (PC Engine) core on the MiSTer, and he has since worked on improving it by adding features like CD support, various controller functionalities, and the CD head seek time delay.
00:04:15 He discusses how reported emulation bugs often turn out to be quirks present in the original games.
00:05:22 He notes that the quality of PC Engine games varied, with a noticeable difference between Japanese and North American releases.
00:06:21 The shift to the CD format in 1992 was driven by lower production costs, allowing for more investment in game development.
00:18:53 David lists his top five PC Engine (including CD) games, which include Ys I & II, Ys IV, Gunhed (Blazing Lazers), Bomberman ’94, and Puyo Puyo CD Tsu.
PC-FX and Virtual Boy
00:09:56 In response to a viewer question, David confirms that his work on the PC-FX CPU could potentially benefit the development of a Nintendo Virtual Boy core for the MiSTer, as they share the same CPU.
00:13:01 The PC-FX was designed to be the successor to the PC Engine but was a commercial failure in Japan, with only about 70 games released.
00:15:58 He points out that the PC-FX had advanced features for its time, such as dual video chips and motion JPEG for full-motion video.
00:59:04 David mentions he is currently working on an optical drive emulator (ODE) for the PC-FX to help with the system’s longevity.
The Terasic DE25-Nano FPGA Board
00:27:03 The DE25-Nano is a new FPGA board that has sparked interest in the MiSTer community. It features a faster ARM processor, DDR4 memory, and onboard SDRAM.
00:27:52 David believes the DE25-Nano could be a valuable development tool due to its improved memory bandwidth and potential for faster compile times.
00:34:01 He suggests a price point between $280 and $320 would be crucial for its widespread adoption.
00:40:06 David notes that the DE25-Nano does not have significantly more logic elements than the DE10-Nano, which will still be a limiting factor for more complex systems.
Future of FPGA Gaming and New Cores
00:45:54 The Replay 2 is another upcoming FPGA board that could be a contender, as it is expected to have double the logic elements of the DE25-Nano.
00:47:44 David’s most desired core is for the PC-FX, and he is actively working on it. He is also interested in improving the X68000 core by adding controller support.
00:50:22 He has already added support for several controllers to the X68000 core and is currently working on adding support for the Cyber Stick.
01:03:09 The interview also mentions the Game Bub, a new open-source handheld FPGA device.
01:13:21 The Icepi Zero is another small FPGA board with retro gaming potential, but it’s more suited for simpler systems.
Core Development and Community Contributions
01:37:51 David offers advice for new developers, suggesting they start by making small modifications to existing cores.
01:43:39 He discusses his close working relationship with SRG320, a prominent core developer, and how he supports their work through testing and feedback.
01:45:31 He recently added CD+G (CD plus Graphics) support to the PC Engine CD core, allowing users to play karaoke discs with on-screen graphics.
01:51:34 David has preserved a large collection of PC Engine magazines by having them scanned and sharing them with the community.
01:58:32 He has also created a small macro pad for taking screenshots on the MiSTer, which is available on his GitHub.