Viewing Issue Advanced Details
ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
03620 Speed Minor Always Dec 31, 2009, 22:29 Jan 7, 2010, 23:12
Tester M.A.S.H. View Status Public Platform MAME (Self-compiled)
Assigned To Resolution Fixed OS Windows XP (32-bit)
Status [?] Resolved Driver
Version 0.135u4 Fixed in Version 0.136u1 Build Normal
Fixed in Git Commit Github Pull Request #
Summary 03620: quasar: Massive slowdown
Description Massive slowdown in attract mode and game. Normal speed in MAME 0.134.
'ACCESS VIOLATION' from MAME 0.134u1 to u4. Fixed ACCESS VIOLATION in
MAME 0.135, but game is very slow
Steps To Reproduce
Additional Information
Github Commit
Flags
Regression Version 0.134u1
Affected Sets / Systems quasar
Attached Files
 
Relationships
related to 03623Resolved  laserbat, catnmous: Massive slowdown 
Notes
4
User avatar
No.05355
Tafoid
Administrator
Dec 31, 2009, 22:45
If I had to guess, the 'internal divide by 15' function is at fault. 0.134u4 first showed the 400khz speed and I assume, the first version that was so slow. Previous version held a 6mhz speed for the i8035.
User avatar
No.05437
etabeta
Developer
Jan 6, 2010, 18:55
edited on: Jan 6, 2010, 19:36
these slow downs are related to some s2650 change happened between 0.134 and 0.134u1 (I just tested this by applying the ACCESS VIOLATION fix to u1). we probably need couriersud to have a proper fix

as an additional note: regression is due to irq handling. I'm going to check if the changes were correct with some s2650 expert...
User avatar
No.05451
Haze
Senior Tester
Jan 7, 2010, 18:37
well, if you use pulse line, there is a chance the interrupt can be missed. If you use hold line, it will be held until the interrupt is taken.

static INTERRUPT_GEN( quasar_interrupt )
{
cputag_set_input_line_and_vector(device->machine, "maincpu", 0x0, HOLD_LINE, 0x03);
}

It could just be that the interrupt handling in the driver is wrong, for IRQs PULSE_LINE is pretty uncommon anyway (it's usually used with NMIs which the hardware has to take regardless)
User avatar
No.05454
etabeta
Developer
Jan 7, 2010, 23:12
Fixed by Quench (which told me how to fix this half an hour before Haze's comment ;) )