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From: mks@cbmvax.commodore.com (Michael Sinz)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: A3000 DATA Cache (Can we PLEASE Settle this?)
Message-ID: <22494@cbmvax.commodore.com>
Date: 17 Jun 91 13:01:58 GMT
References: <1991May26.091925.20814@news.iastate.edu> <21999@cbmvax.commodore.com> <274.2857ae21@intersil.uucp> <22458@cbmvax.commodore.com> <276.285b897c@intersil.uucp>
Reply-To: mks@cbmvax.commodore.com (Michael Sinz)
Distribution: na
Organization: Commodore, West Chester, PA
Lines: 64

In article <276.285b897c@intersil.uucp> hamilton@intersil.uucp writes:
>In article <22458@cbmvax.commodore.com>, daveh@cbmvax.commodore.com (Dave Haynie) writes:
>> In article <274.2857ae21@intersil.uucp> hamilton@intersil.uucp writes:
>>
>>>my machine has always booted with : (INST: CACHE NOBURST) (DATA: NOCACHE
>>>NOBURST) in (Set)CPU's words.
>>
>> I can think of three reasons this might be happening:
>>
>> 1) The software guys changed it and didn't tell anyone.
>>
>> 2) You're running a really old version of 2.0x.
>>
>> 3) You have the latest ROM image on disk, but an old version of SetPatch.
>>
>> 4) You have "SetCPU data nocache" or some-such buried somewhere in your
>>    startup-sequence.
>
>Ok, here are the specifics:
>
>I'm running an A3000 with KS V37.175, WB V37.52, and SetPatch V37.6.
>
>I just re-wrote my startup-sequence so the very first three lines are:
>
>	CPU
>	SetPatch
>	CPU
>
>When I rebooted, CPU reported "(INST: Cache NoBurst) (DATA: NoCache NoBurst)"
>both times.
>
>So it's not SetPatch, it's not my startup-sequence, and I believe V37.175
>is pretty recent (but I've been seeing this since KS V36.something anyway).
>So what could it be?

The SetPatch that I use is 37.9  It I don't think that 37.6 had the CACHE
thing in it.  (You can tell if SetPatch has the extra NOCACHE option.
Try SetPatch ?  to see...)

>I'm perfectly happy just putting "CPU cache burst" in my startup-sequence
>if that turns out to be the answer, but I'm really curious as to why my
>machine (and the few friends I have who also have 3000s) seems to boot
>up with everything disabled except the instruction cache.  Thanks for
>any ideas...

You do not really want burst on the data cache.  Overall, it is a speed loss.
Also, if you do not have SCRAM, it may be a bad idea to burst at all since
a burst transfer is just as slow as a normal transfer.

The default bootup values are:

System: 68030 68882 FastROM (INST: Cache Burst) (DATA: NoCache NoBurst)

(Note that FASTROM is due to SuperKickstart...)

			-- Mike

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|      /// Michael Sinz  -  Amiga Software Engineer                    |
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