89C51ED2
in [Design]
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From: Joerg on 5 Sep 2008 09:18 Eeyore wrote: > > Joerg wrote: > >> Eeyore wrote: >>> Joerg 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 think Atmel actually do an app note on that. >> When it comes to POR/BOR I do not trust manufacturers much. Learned some >> hard lesson in life. > > Care to share ? > I don't remember all the gory details but until recently none of the uC had a decent reset. Weird effects until I rolled my own. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: MooseFET on 5 Sep 2008 09:49 On Sep 4, 9:29 pm, Eeyore <rabbitsfriendsandrelati...(a)hotmail.com> wrote: > MooseFET wrote: > > "TT_Man" <Some...(a)ntlworld.com> wrote: > > > > How does the defect manifest itself ? > > > > > 8051s have been 'rock solid' IME. As someone else memtioned, do you have a > > > > critical timing issue anywhere ? Like an I/F chip maybe ? Are PSEN, ALE, > > > > /WR > > > > and /RD all clean ? You're probably not using PSEN but never hurts to > > > > check. > > > > > No-one's messed about with the clock oscillator parts have they ? > > > > > What do the 10 lines of code do ? > > > > > Graham > > > > An extra speech phrase is output.... ALE PSEN /wr/rd are all unused as the > > > device is a 64K flash part. We have several generations of board that all > > > support various chip types, 52, 53 ED2 etc. The faulty ED2's will not > > > execute correctly in any board. > > > The 10 lines of code basically index a speech phrase and output it 3 times > > > to a dac. Then the routine checks an input and proceeds or not via a branch. > > > somewhere in these lines of code, another speech phrase is output. Speech is > > > terminated via a null byte. The extra speech phrase in not contiguous with > > > the correct phrases, so it's not going to be a DPHL corruption...that > > > somehow skips the null byte detection. > > > Does the code have interrupts enabled? > > > Is it written in ASM or C? > > I think he said it was all written in asssembler <yuk>. On an 8051, asm is really the way to go. The OP was making comments about DPTR so I suspected asm but vagueness of his descriptions sounded like a C programmer who doesn't really know what is going on under the hood. Many C compilers overlay variables on the 8051 if he is doing interrupts in C code he may be running a routine in the interrupt code that overlays one of his variables. > > Graham
From: TT_Man on 5 Sep 2008 11:01 >> > Does the code have interrupts enabled? >> >> > Is it written in ASM or C? >> >> I think he said it was all written in asssembler <yuk>. > > On an 8051, asm is really the way to go. The OP was making comments > about DPTR so I suspected asm but vagueness of his descriptions > sounded like a C programmer who doesn't really know what is going on > under the hood. Many C compilers overlay variables on the 8051 if he > is doing interrupts in C code he may be running a routine in the > interrupt code that overlays one of his variables. > > >> >> Graham > Not a prayer in hell 100% assembler. :)
From: MooseFET on 5 Sep 2008 12:03 On Sep 5, 11:01 pm, "TT_Man" <Some...(a)ntlworld.com> wrote: > >> > Does the code have interrupts enabled? > > >> > Is it written in ASM or C? > > >> I think he said it was all written in asssembler <yuk>. > > > On an 8051, asm is really the way to go. The OP was making comments > > about DPTR so I suspected asm but vagueness of his descriptions > > sounded like a C programmer who doesn't really know what is going on > > under the hood. Many C compilers overlay variables on the 8051 if he > > is doing interrupts in C code he may be running a routine in the > > interrupt code that overlays one of his variables. > > >> Graham > > Not a prayer in hell 100% assembler. :) Are you using interrupts?
From: Rich Grise on 5 Sep 2008 12:07
On Fri, 05 Sep 2008 04:33:14 +0100, Eeyore wrote: > Rich Grise wrote: > >> If I could get an 8051 equivalent but with Motorola's timer system (see >> 68HC11, e.g.), I'd be in hog heaven. ;-) > > What's so great about Motorola's timers ? It's way, way, easier to use than the 8051's simple little counter. At least I found it to be so. I've done 8051 (8035 + eprom, actually) and 68HC11, and the 68HC11 makes the 8051 look like a boat anchor. ;-) Cheers! Rich |