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From: ervin@pinbot.enet.dec.com (Joseph James Ervin)
Newsgroups: comp.sys.handhelds
Subject: Re: Interesting effect (HP48)
Message-ID: <20244@shlump.nac.dec.com>
Date: 14 Feb 91 21:57:33 GMT
References: <59716@eerie.acsu.Buffalo.EDU> <1991Feb14.193917.3886@portia.Stanford.EDU>
Sender: newsdaemon@shlump.nac.dec.com
Reply-To: ervin@pinbot.enet.dec.com (Joseph James Ervin)
Followup-To: Interesting effect (HP48)
Organization: Digital Equipment Corporation
Lines: 12

>It could be a 'soft error', which is simply the interaction of radiation
>with the memory, causing a temporary read error.  I've worked in memory
>failure analysis before, and soft errors are enough of a problem that they
>are used as a measure of the robustness of a new design.  

I believe you can pretty much rule out alpha particles as a source of the
errors you've seen.  Such "soft" errors are a phenomenon of dynamic
memory devices.  The memory in the HP48 is static, so alpha particles
have a much, much, much smaller chance of doing any bit-flipping than
in the case of dynamic memory.

>>>Joe Ervin