04187: colmns97: Missing sound

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
04187	Sound	Minor	Always	Jan 15, 2011, 01:33	Oct 20, 2018, 13:41

Tester	M.A.S.H.	View Status	Public	Platform	MAME (Self-compiled)
Assigned To		Resolution	Open	OS	Windows XP (32-bit)
Status [?]	Confirmed			Driver	sega/saturn.cpp
Version	0.141	Fixed in Version		Build	Normal
		Fixed in Git Commit		Github Pull Request #

Summary	04187: colmns97: Missing sound
Description	Sound is missing in Columns '97 since MAME 0.126u3. In 0.126 the sound works and 0.126u1 and u2 the game crashed.
Steps To Reproduce
Additional Information	The crash first came about due to the installation of the SH2 DRC in 0.126u1 (r2211) The fix for the crash didn't fix the sound in 0.126u3 (r2328) stv.c merged into saturn.c in 0.142u2
Github Commit

Flags
Regression Version	0.126u1
Affected Sets / Systems	colmns97

Attached Files

No.10010 Osso Moderator Nov 21, 2013, 17:33	It now displays "SCSP MCIEB enabled ffff, contact MAMEdev" right after the patents screen.
No.15587 Kale Developer Oct 20, 2018, 13:41 edited on: Oct 27, 2018, 15:49	SCSP MCIEB is a side effect of what the game is trying to do behind the curtains. Basically it sends an illegal DMA operation to sound section, causing the lack of sound and those messages. ETA: Several SCU DMAs are sent to sound RAM sections, most of them with a size of 0xfffff***. DMA lv 0 max size is known to be 0xfffff, so this is supposed to be an illegal op. Might be a SH2 cache issue or a SCU side effect when choosing that size (backwards? autocorrected?) fwiw these are the values that the game sends (and a presumed next offset, since I totally suppose that the ending transfer must be linear or close anyway). (at sega logo) dst wrong_size next_offset 5a14fa0 ffb49 c2ce 5a2126e ffbac 9bac 5a2ae1a ffcc2 dcc2 5a38adc ffba8 c9a8 5a45484 ffaa8 c0a8 5a5152c fff84 c614 5a5db40 ffacc ???? === (on easy selection) 5a065d6 ffb44 ????

No.10010

Osso

Moderator

Nov 21, 2013, 17:33

It now displays "SCSP MCIEB enabled ffff, contact MAMEdev" right after the patents screen.

No.15587

Kale

Developer

Oct 20, 2018, 13:41

edited on: Oct 27, 2018, 15:49

SCSP MCIEB is a side effect of what the game is trying to do behind the curtains. Basically it sends an illegal DMA operation to sound section, causing the lack of sound and those messages.

ETA: Several SCU DMAs are sent to sound RAM sections, most of them with a size of 0xfffff***.
DMA lv 0 max size is known to be 0xfffff, so this is supposed to be an illegal op. Might be a SH2 cache issue or a SCU side effect when choosing that size (backwards? autocorrected?)
fwiw these are the values that the game sends (and a presumed next offset, since I totally suppose that the ending transfer must be linear or close anyway).

(at sega logo)
dst     wrong_size next_offset
5a14fa0 ffb49      c2ce
5a2126e ffbac      9bac
5a2ae1a ffcc2      dcc2
5a38adc ffba8      c9a8
5a45484 ffaa8      c0a8
5a5152c fff84      c614
5a5db40 ffacc      ????
===
(on easy selection)
5a065d6 ffb44      ????