05077: All playable sets in missile.c: Graphics corrupt in Missile Command

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
05077	Graphics	Major	Always	Dec 1, 2012, 16:28	Dec 20, 2012, 13:38

Tester	Zaghadka	View Status	Public	Platform	MAME (Self-compiled)
Assigned To	Phil Bennett	Resolution	Fixed	OS	Windows Vista/7 (64-bit)
Status [?]	Resolved			Driver	atari/missile.cpp
Version	0.147u3	Fixed in Version	0.148	Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	05077: All playable sets in missile.c: Graphics corrupt in Missile Command
Description	Random specs appear across the playfield when executing any of the working missle.c games.
Steps To Reproduce	Launch game and wait.
Additional Information
Github Commit

Flags
Regression Version	0.147u3
Affected Sets / Systems	All playable sets in missile.c

Attached Files

No.09113 Zaghadka Tester Dec 1, 2012, 16:42	Tried playing for a few minutes with all the snow on the screen. Sounds eventually become corrupted, and then I had an emulation reset occur around the 4x wave. The black background turned to white when this happened.
No.09131 Phil Bennett Developer Dec 10, 2012, 14:41	The problem lies with the delayed VRAM write-enable hack in get_madsel(). Since the 6502 core became cycle-accurate the hack no longer works correctly.
No.09144 Phil Bennett Developer Dec 20, 2012, 13:38	VRAM accesses were being lost whenever an instruction occurred either before or during an interrupt. The new MADSEL handling fixes this.