89C51ED2
in [Design]
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From: Joerg on 3 Sep 2008 16:22 Jim Thompson wrote: > On Wed, 03 Sep 2008 12:54:56 -0700, Joerg > <notthisjoergsch(a)removethispacbell.net> wrote: > >> TT_Man wrote: >>> Anyone using this part experiencing problems? we have used them for 4 years >>> or so. Date codes up to 0705 work ok, 0814 misbehaves....same chip, same >>> software, 0814 doesn't execute properly... >>> >> Did you check the POR situation? Maybe issue a nice long POR and see if >> it'll run? >> >> The POR circuit on most 8051 is %^&#!! <tantrum censored> so I always >> rolled my own. As for BOR, I think many uC designers don't know what >> that means ... > > I do ;-) I have some really nice designs, but you can't duplicate > them in discrete form :-( > Meantime some pretty good POR/BOR chips have shown up. That was different in the 90's where you just couldn't trust many of them. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Rich Grise on 3 Sep 2008 17:39 On Wed, 03 Sep 2008 12:54:56 -0700, Joerg wrote: > ... > The POR circuit on most 8051 is %^&#!! <tantrum censored> so I always > rolled my own. As for BOR, I think many uC designers don't know what > that means ... Body Odor Reset? ;-) Cheers! Rich (my "real" guess is brown-out. ;-) )
From: mpm on 3 Sep 2008 17:42 On Sep 3, 1:13�pm, "TT_Man" <Some...(a)ntlworld.com> wrote: > Anyone using this part experiencing problems? we have used them for 4 years > or so. Date codes up to 0705 work ok, 0814 misbehaves....same chip, same > software, 0814 doesn't execute properly... Is this an Atmel part? If so, I would check the datasheets for updates. I know on their 8252/3 series, they made a change to the crystal cap requirements. Went from 30pf to around 5pf. Would occasionally cause improper startup/reset, and very slow operation if it did reset. If they changed the oscillator on ED2, that could very well be the problem. (?) -mpm
From: Joerg on 3 Sep 2008 17:46 Rich Grise wrote: > On Wed, 03 Sep 2008 12:54:56 -0700, Joerg wrote: >> ... >> The POR circuit on most 8051 is %^&#!! <tantrum censored> so I always >> rolled my own. As for BOR, I think many uC designers don't know what >> that means ... > > Body Odor Reset? ;-) > > Cheers! > Rich > (my "real" guess is brown-out. ;-) ) > Bacardi on the rocks :-) -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 3 Sep 2008 17:56
mpm wrote: > On Sep 3, 1:13�pm, "TT_Man" <Some...(a)ntlworld.com> wrote: >> Anyone using this part experiencing problems? we have used them for 4 years >> or so. Date codes up to 0705 work ok, 0814 misbehaves....same chip, same >> software, 0814 doesn't execute properly... > > Is this an Atmel part? > If so, I would check the datasheets for updates. > I know on their 8252/3 series, they made a change to the crystal cap > requirements. > Went from 30pf to around 5pf. Would occasionally cause improper > startup/reset, and very slow operation if it did reset. If they > changed the oscillator on ED2, that could very well be the problem. > (?) > Hopefully not without changing the rev level and informing their customers? Yikes, I sure hope not. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |