I decided that I'd like to have a ROM of Blue Sphere that wasn't S&K + S1. I started by messing with the init routines in S&K, and got a Sonic & Knuckles ROM that booted immediately into Blue Sphere without a lockon ROM. Then I took a different approach, starting from a file with just the init code, and copying from S&K's ASM until the ROM built. This produced a 0.99MB ROM, of which 48% is padding, because the sound driver requires specific addresses. So yeah, it's Blue Sphere, alone. You can download it from the wiki: Blue Sphere Standalone ROM. ------- Now, I've added some new features, which are available here: Blue Sphere Plus
Cool stuff, though I gave it a go on my Mega Drive, and well, every time a sound effect is played, it completely messes with the music, it sounds as though it's sped it up by x400 or something, and in time, just stopped, no sound.
I'm surprised it actually runs on a console. I only tested it on Gens/GS, where it works fine. But, all the sound stuff should be at the exact same place as it is in S&K, so I have no idea what could be causing that.
Updated: On the menu, pressing A, B or C now cycles between Sonic, Tails and Knuckles. Tails is represented by one blue and one red bumper.
I don't know if you are doing it already, but it may be possible to cut down padding by using the assembled sound driver instead of the preassembled one. In the SVN disassembly, if you cut out lines 207793-208299 and line 208301, you get the assembled sound driver; this driver does not need specific locations for the music other than the banks being aligned at a $8000 byte boundary.
Thanks for this. I didn't even know it was possible to emulate Blue Sphere, embarrassingly. (Well, I knew it was possible, I just didn't know what rom to use)
Normally one would emulate Blue Sphere by locking Sonic 1 onto Sonic & Knuckles ("copy /b sk.bin+s1.bin sphere.bin" in the windows command prompt). Edit: I tried adding SRAM support, but I have no idea where the stage number is stored.
Proof that I don't adequately test things. Fixed. And, now has SRAM support to remember the character you selected.
I was going through stages with my blue sphere editor, and I found a crash in your ROM It seems that the results screen crashes when the difficulty counter hits 7. Here is a code of a pretty easy max skill level for you to test on. Code: 3348-4270-1748
For me it crashes when the difficulty number hits 8 (Chickens). But I have no idea how to debug this. Edit: It still crashes if I comment out the first two lines of Obj_Difficulty_2CD26, leaving only jmp (Delete_Current_Sprite).l Edit2: Oh, it's because I blindly copied the routine without noticing it doesn't end with rts and continues into the next subroutine.
Fixed. And now Tails has orange icons on the title menu instead of one blue and one red. And, if you hold A while pressing start to start a stage, you'll start all stages from then on at top speed (not saved between sessions).
Updated, now you can select Sonic + Tails (one blue and one orange icon) and Knuckles + Tails (one red and one orange icon).