FFF3 = 01 There you go. Nothing too impressive to be honest, it just shows some stats on screen. Notice the fact that it uses the same RAM variables for cheats as the sonic engines; which isn't a coincidence as you might know I don't know if this was already known (I couldn't find it anywhere else), so trash it if so.
I still stand firmly by the belief that a majority of the stuff in Sonic 1 is built off the official SDK for the Genesis, one way or another (or at least SOME kind of SDK, of sorts...). It uses the SMPS (Sample Music Playback System), common compression algorithms are shared with a lot of other games; and, nearly all these formats used in Sonic are found alongside each other in other games that use them (I.e, a game using both Kosinski and Nemesis compressions... etc). To clarify further: I think the Sonic engine isn't exactly an original engine, but rather a modification of some sort of stock Sega engine. It certainly makes sense.
Of course, is obvious that no game from a comercial entreprise is written completely from scratch, if you count libraries, macros, and all that stuff. But this case concretely (s1-gg relation) is more interesting considering that both games were programmed (well, reprogrammed in the case of gg) by the same man :P
I'm fairly sure it was. I remember L0st posting a pic of it, and it might have been brought up in another GnG post I made at the X-Cult forums a while ago (about an unused cheatcode present inside the ROM). For those who didn't know, this game was also programmed by Naka. There might be some similar debug mode in Phantasy Star, by the way...
What started as a search for the debug mode in PSII ended up in this thread: http://forums.sonicretro.org/index.php?showtopic=9116 :P But in short, no, the cheat "system" used in S1 and GG isn't used in any other game, apparently.
I always thought there was some relation because GnG also has the slow-motion trick with the exact button combinations (B to animate, C to advance-frame). And it has the UDLR code combination for level select and AAAAUDLR for debug on the title screen. Interesting stuff.
