Home Page Forums MAME MAME a7800 & Two Independent Buttons Recognition

I filed under Bugzilla - but that seems to be a casualty of the server crash as well.

Tested under MESS 0.145u1 64-bit and MESS 0.111 32-bit Windows and the same issue is present.

MESS does not correctly identify 2 independent buttons for the following games:

Scramble - 1st/left button = missles & 2nd/right button = bombs
RipOff - 1st/left button = fire & 2nd/right button = thrust

The behavior for both titles instead translates as if only one button controller is present resulting in the following:

Scramble - 1st/left button = missiles and bombs & 2nd/right button = missiles and bombs
RipOff - 1st/left button = fire & 2nd/right button = fire
*Joystick Up now serves as thrust.


Both games behave correctly under the ProSystem emulator and on the real hardware. For some reason, under MESS, the behavior is as if a one button controller was only present.

Additionally, if you need an "official" original release title with the same behavior issue, plese see Asteroids.

MESS uses 'down' as hyperspace whereas if you have a two-button joystick, hyperspace is mapped to the second button.

The game is behaving as if only a one button controller is present.

I think I fixed it, patch submitted soon. Pin 6 of the controller port is the input for reading the button on a single button joystick. For two button controllers it's an output and is held high by the RIOT chip. The emulation was missing this.

Awesome! Thank you for looking at this and fixing it. It is very much appreciated!

No problem, patch submitted I'm still missing the TIAEN signal (2600 mode switch?), but I don't think that's needed as the driver is always in 7800 mode.

Thanks again, it is very much appreciated.

It would be very cool if down the road you launch a 2600 ROM under a7800, and the driver recognizes it, causing the switch to 2600 mode. I mean not just as some batch or patch to kick off the a2600 driver, but truly reading the ROM under the a7800 driver and in turn utilizing the 2600 emulation.

Which honestly, I'm not sure if what I'm stating is clear or just a matter of semantics. And if I recall correctly, it's not a matter of the 7800 reading a 2600 game, as it is looking for the 7800 signature in a game. If the signature is not there, I believe the instructions then is to disable Maria and kick off 2600 graphic mode.

In any event, obviously it is a minor thing and more important is fixing actual 7800 emulation specific bugs first.

I think the 7800 diag cart is the only thing that utilizes both 7800 and 2600 modes.

Mitch

Huygens, thanks a million!!! Just tried 0.145u5...RipOff, Scramble, and Asteriods function as they should with two independent buttons...Excellent work!