Issues with some Living Books games & SheepShaver (no audio)

About SheepShaver, a PPC Mac emulator for Windows, MacOS X, and Linux that can run System 7.5.3 to MacOS 9.0.4.

Moderators: Cat_7, Ronald P. Regensburg, ClockWise

Post Reply
User avatar
celebi23
Granny Smith
Posts: 101
Joined: Wed Jun 18, 2008 5:53 am

Issues with some Living Books games & SheepShaver (no audio)

Post by celebi23 »

So, I've got a MacBook Pro running 10.9.5. I'm running Mac OS 7.5.5 in SheepShaver (Version 2.4.20140201). I've got almost all the Living Books games running in it. Almost all of them run perfectly ok. There are 4 that don't play any sound at all though:

My own copy of Stellaluna
My own copy of The Berenstain Bears in the Dark
http://macintoshgarden.org/games/green-eggs-and-ham
http://macintoshgarden.org/games/little ... -at-school

These 4 games have a folder of Mac extensions (Sound Manager 3.1, QuickTime 2.1 & Thread Manager 2.0.1). The System folder already has newer versions of those extensions installed. Can't figure out why sound won't play at all with these games. Is this a known issue?
User avatar
adespoton
Forum All-Star
Posts: 4227
Joined: Fri Nov 27, 2009 5:11 am
Location: Emaculation.com
Contact:

Re: Issues with some Living Books games & SheepShaver (no au

Post by adespoton »

Not a known issue with those particular games, but if you search the forum for "no audio" or "no sound" you'll find a number of other similar cases.

In at least one case, the issue was fixed by using the older extensions provided with the games -- but this required an initial install that didn't include the newer extensions (Quicktime updates more than you may think).

Your best bet is probably to roll back to System 7.1 and install the games on top of that. Otherwise, you're going to have to do a messy "find all the newer extensions and their kin and disable them" surgery prior to installing the older ones, and then it still might not work on 7.5.5.
Jorpho
Master Emulator
Posts: 380
Joined: Fri Sep 17, 2004 4:22 am

Re: Issues with some Living Books games & SheepShaver (no au

Post by Jorpho »

Aren't some or all of those also supported by ScummVM? (I know that's not terribly helpful, but if you just want to get them running, then that would be the way to go.)
User avatar
celebi23
Granny Smith
Posts: 101
Joined: Wed Jun 18, 2008 5:53 am

Re: Issues with some Living Books games & SheepShaver (no au

Post by celebi23 »

adespoton wrote:Not a known issue with those particular games, but if you search the forum for "no audio" or "no sound" you'll find a number of other similar cases.

In at least one case, the issue was fixed by using the older extensions provided with the games -- but this required an initial install that didn't include the newer extensions (Quicktime updates more than you may think).

Your best bet is probably to roll back to System 7.1 and install the games on top of that. Otherwise, you're going to have to do a messy "find all the newer extensions and their kin and disable them" surgery prior to installing the older ones, and then it still might not work on 7.5.5.
Hmm, I guess I'll have some digging to do :P Thanks for the suggestions.

Jorpho wrote:Aren't some or all of those also supported by ScummVM? (I know that's not terribly helpful, but if you just want to get them running, then that would be the way to go.)
Yeah, some of them are. But, they don't run perfectly. Like the ones that have mini games don't work or there are weird quirks in how they run in ScummVM. I like having them all in a SheepShaver VM image. I even whipped up a HyperCard launcher for the games :P
Jorpho
Master Emulator
Posts: 380
Joined: Fri Sep 17, 2004 4:22 am

Re: Issues with some Living Books games & SheepShaver (no au

Post by Jorpho »

celebi23 wrote:Yeah, some of them are. But, they don't run perfectly. Like the ones that have mini games don't work or there are weird quirks in how they run in ScummVM.
Perhaps you should inform the devs if they're not already aware?
I like having them all in a SheepShaver VM image.
To be clear, System 7.1 won't run in Sheepshaver.
User avatar
adespoton
Forum All-Star
Posts: 4227
Joined: Fri Nov 27, 2009 5:11 am
Location: Emaculation.com
Contact:

Re: Issues with some Living Books games & SheepShaver (no au

Post by adespoton »

Oh yes... I conflated SS and BII for a second there. You need the PPC version of 7.1.2 (different than the 68k version, it was bundled with the Power Macintosh 6100/7100/8100 and never had a retail release) to be able to run in SheepShaver, and that's not guaranteed to work well, as you need the PM 6100/7100/8100 ROM as your SS boot ROM and that's not the ROM used in SheepShaver development. Officially, and in the SheepShaver documentation, it only "runs MacOS 7.5.2 thru 9.0.4."

Living Books software is almost all 68k, and if you run it in SheepShaver, you're running the game in its 68k interpreter which is then emulated by the PPC CPU which is in turn emulated by SheepShaver. It makes system calls which were designed for System 7.1, which later systems then attempt to interpret correctly, and the PPC calls are usually just wrapped 68k calls.

I'm going to try this weekend to see if I can get that ROM/OS combo to work under SS to provide a definitive statement; possibly I can even try out one of those living books to see if this fixes the sound issue.

Long and short is: it's amazing it runs at all in SheepShaver under 7.5.5. Better to use Basilisk II or submit a bug to the ScummVM guys to fix the issues in their interpreter, neither of which will let you run it under SheepShaver with sound.

[edit]

The PowerMac 6100/7100/8100 series has the following specs:
Processor: 601, 60
PMMU: integrated
FPU: integrated
Data Path: 64, 30
L1 Cache: 32K
L2 Cache: opt'l.
2nd Processor: opt. Intel 486DX2-66
Slots: one 7" NuBus or PDS

As such, we need to ensure that anything emulating it can emulate the PPC601 instruction set, the PMMU and the FPU. We already know that a lack of PMMU in SS prevents it running in Mac OS 9.1+, and the fact that it was written against a PowerMac 9500 using a PPC604 CPU (it is hard-coded to identify as a 9500 and emulates the 604), means that attempting to emulate a 601 CPU and run an OS that the 9500 doesn't support is likely an exercise in futility, especially if 7.1 uses the PMMU (I know it's got some proprietary stuff in there, which is why Apple was able to make 7.0.x and 7.5.x freely available, but not 7.1.x).

Maybe if I ever get a block of time, I should see if I can tweak SheepShaver to run as a 6100 with a 601 CPU.
Pruten has emulated enough of the 68851 PMMU to boot A/UX, so maybe this is enough of an outline of how an MMU works to boot System 7.1 on PPC too... the code isn't compatible with the structure used in SS or the 601+, but it could possibly be used as documentation to re-implement (and hey... maybe that would make 9.1+ work too?).

For those interested, the PMMU datasheet is here, the 601 user guide is here and the PPC architecture primer is here (see Table 9).

I think I may be hijacking the thread with blue sky ideas now though :)
Post Reply