01806: smashtv4: Pcb bug not reproducible in mame

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
01806	Gameplay	Minor	Have not tried	May 15, 2008, 18:36	May 17, 2008, 16:39

Tester	Kold666	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	No change required	OS	Windows XP/Vista 32-bit
Status [?]	Closed			Driver	midway/midyunit.cpp
Version	0.125u1	Fixed in Version		Build	Normal
		Fixed in Git Commit		Github Pull Request #

Summary	01806: smashtv4: Pcb bug not reproducible in mame
Description	On my Smash Tv (rev 4.00) if you try to push FIRE UP togheter with FIRE DOWN during gameplay, which is impossible if you use a joystick like on the original cabinet, the screen goes black even if the game is playing in background and you have to wait the gameover to have it reappear again. This happens only during gameplay, not during attract mode. It doesn't happen if you push togheter FIRE LEFT and FIRE RIGHT In mame I can't reproduce this bug
Steps To Reproduce
Additional Information
Github Commit

Flags	Verified with Original
Regression Version
Affected Sets / Systems	smashtv4

Attached Files

No.00968 Tafoid Administrator May 15, 2008, 19:02	I tried mapping both up and down fire to the same key.. no crash or black screen happened. I'm not sure if the input system has a failsafe to disallow such odd mapping or not - I'll let Aaron or someone else knowledgeable with the input system to comment if MAME is truly allowed to do those types of movements if the same key is mapped in two incompatible directions.
No.00974 aaron Developer May 15, 2008, 20:15	This is because there is code in the MAME input system to ensure that you can't push up and down at the same time for joystick inputs. This is by design.
No.00996 Haze Senior Tester May 17, 2008, 16:20	I think this behavior should be optional, with a global option to turn it on / off. Obviously in most cases it is desirable to prevent this, as there are a significant number of games which break with this behavior. (because it was assumed to never happen) However, in the interest of testing, and verification agianst the real PCB, it would be nice if there was a simple way to turn it off, without editing the code. I wanted to test Guru's Metal Slug 5 report, but never got around to it because it required a recompile and I didn't have the source handy. There are also some systems (NeoCD IIRC) that have a secret debug menu, which requires pressing conflicting directions to access, probably because they assumed no actual user of the system would be able to. With the current MAME code you can't test this without changing the code and recompiling
No.00998 Tafoid Administrator May 17, 2008, 16:39	This kind of disabling of the input restrictions would also allow for such arcade behavior as described about Space Invaders: http://www.mameworld.info/ubbthreads/showthreaded.php?Cat=&Number=149607 Then again, I don't think there is an left<>right control input in MAME that isn't considered a joystick in some aspect (2-way joystick). There probably should be an input that knows the control panel is buttons rather than a stick so such movement is possible. i supposed if you can do it in an arcade game, you should be able to do it in MAME.