Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!apple!bionet!agate!violet.berkeley.edu!steve
From: steve@violet.berkeley.edu (Steve Goldfield)
Newsgroups: comp.sys.mac
Subject: Re: 68851 PMMU Test?
Message-ID: <25656@agate.BERKELEY.EDU>
Date: 21 Jun 89 16:09:25 GMT
References: <134@nisca.ircc.ohio-state.edu> <383@taniwha.UUCP>
Sender: usenet@agate.BERKELEY.EDU
Distribution: comp.sys.mac
Organization: University of California, Berkeley
Lines: 29

In article <383@taniwha.UUCP> paul@taniwha.UUCP (Paul Campbell) writes:
#>In article <134@nisca.ircc.ohio-state.edu> bobd@hpuxa.ircc.ohio-state.edu (Bob DeBula) writes:
#>>Well, I got my 68851 PMMU installed in my MAC-II, now (without buying
#>>Virtual or A/UX) does anyone know how to test it?  I'm planning on waiting
#>>until System 7.0 to actually exploit it, but I would like to assure myself
#>>that it's properly installed and functioning. Any ideas netters?  
#>
#>actually a very simple (and quite good) test is to plug in the PMMU and
#>turn the Mac on. If you get a happy Mac the the PMMU is OK (they actually
#>have to use the PMMU to map to the crazy 24-bit addressing ....). Of
#>course this does not test all the internal functions of the PMMU but
#>at least you know the TLB works and that it walks page tables etc
#>
#>	Paul
#>
#>Paul Campbell, Taniwha Systems Design	UUCP:		..!mtxinu!taniwha!paul 
#>Oakland CA				AppleLink:	D3213
#>Q: How many men does it take to pilot the Exxon Valdez?
#>A: One and a fifth.

I also installed a 68851 PMMU and a 68882 in my Mac II. I've also
been wondering if I was successful. Are you suggesting that
because I was able to turn the machine back on with everything
functioning, that means both chips are properly installed?
I'll admit I was relieved that the system seemed unaffected,
but is it possible for something to be wrong with one or
both of the chips without a visible problem?

Steve Goldfield