Super Stunt Cycle Source Code

[+Trebor]

12 hours ago, Tempest said:

Oh I see. That's not moire effect, that's just how the road is then after you start going off to the left or right?

Correct regarding the effect on the road. 

Pushing left or right on the second controller has no effect.  

Whether pushing up or down on the second controller, it changes the screen in the one direction shown.

[RevEng]

Just for context...

• pushing up on the joystick looks to the game like half of the buttons on the Top Rider controller are engaged. (all of the even bits in the 18-bit controller state are high)
• pushing down on the joystick looks to the game like the other half of the buttons on the Top Rider controller are engaged (all of the odd bits in the 18-bit controller state are high)

i'm sure some of those bits being engaged simultaneously are mutually exclusive (e.g. lean left+lean right) so we can't really expect to get anything resembling the actual control scheme using just a joystick.

 

[Tempest]

I wonder if there's anything else in these demos or if this is it?  I'm guessing this is all.

 

Btw why does the road look crude (with square edges like a 2600 game) when you fire it up in the emulator but looks normal in the video?  Is this another emulation bug?

[RevEng]

i don't think there's anything more here either.

 

@Trebor might want to confirm what the road looks like at the very start of the rom being launched. If the road is dead center and the bike isn't accelerating, like in emulation, I suspect the road looks pretty much the same. The small road ripples in the road are probably there because the bike is supposed to be moving forward, and it's not possible to convey forward acceleration on a mathematically perfect and uniform road.

[+Trebor]

11 hours ago, RevEng said:

@Trebor might want to confirm what the road looks like at the very start of the rom being launched. If the road is dead center and the bike isn't accelerating, like in emulation, I suspect the road looks pretty much the same. The small road ripples in the road are probably there because the bike is supposed to be moving forward, and it's not possible to convey forward acceleration on a mathematically perfect and uniform road.

I made another recording, trying my best to capture the image that appears as soon as the 'Pause' button is hit on the console to launch the ROM from the MCP Dev Cart. 

 

The changing road shift happens very quickly, but from the recording it can be seen.  After the screen flash the road is definitely more centered, including a bulky/chunk residual effect towards the bottom, under the handlebars, as well.

 

If we were able to see the screen/ROM behavior between 8.91 - 9.12 seconds, there's little to no doubt the road would be further centered, and if a frozen/still image when initialized was possible, it would be seen exactly or near exact as shown under A7800 emulator.

 

 

Before the above, at 09.10 seconds and less is screen flashing, transitioning, and fading:

 

[RevEng]

27 minutes ago, Trebor said:

If we were able to see the screen/ROM behavior between 8.91 - 9.12 seconds, there's little to no doubt the road would be further centered, and if a frozen/still image when initialized was possible, it would be seen exactly or near exact as shown under A7800 emulator.

Thanks for the investigation, and I agree.

[Tempest]

Thanks for all the investigation on these.  Is the code for 10/14/88 or 11/18/88 compilable or is something missing from those archives?

[RevEng]

7 hours ago, Tempest said:

Thanks for all the investigation on these.  Is the code for 10/14/88 or 11/18/88 compilable or is something missing from those archives?

It looks to be complete, but the assembler syntax differs from dasm a fair bit, so assembling it would take a bunch of translation work.

 

There is an interesting bit of source in the 10-14-88 source directory, namely the AB1.S and AB2.S files. These aren't a buildable game or demo (there are other files they rely on that aren't  present) but these two files appear to be part of an "Airball 7800" port. (perhaps this Airball) 

 

Here's the header at the top of the files...

;       ****     (C)1988   Property of John Boeschen & Co.      ****
;               ****    Source Code - Airball 7800      ****

 

Often enough programmers will copy over existing source into a new project directory, to have all of their handy routines ready to copy and paste or adapt. I expect the author did so here

[Tempest]

2 hours ago, RevEng said:

It looks to be complete, but the assembler syntax differs from dasm a fair bit, so assembling it would take a bunch of translation work.

 

There is an interesting bit of source in the 10-14-88 source directory, namely the AB1.S and AB2.S files. These aren't a buildable game or demo (there are other files they rely on that aren't  present) but these two files appear to be part of an "Airball 7800" port. (perhaps this Airball) 

 

Here's the header at the top of the files...

;       ****     (C)1988   Property of John Boeschen & Co.      ****
;               ****    Source Code - Airball 7800      ****

 

Often enough programmers will copy over existing source into a new project directory, to have all of their handy routines ready to copy and paste or adapt. I expect the author did so here

Yes it's that Airball.  I didn't know JB&C were working on it.  I guess this proves that it existed at one point.  Neat!

 

I wonder if JB&C and Bluesky Software were related?

[+Mitch]

2 hours ago, RevEng said:

It looks to be complete, but the assembler syntax differs from dasm a fair bit, so assembling it would take a bunch of translation work.

 

ST emulator and Madmac is probably still the easiest way to compile it.

 

Mitch