You can *probably* replace the EEPROM with an FRAM chip (or even a free sample of an FRAM chip) to get around the wear issues. I haven't opened my unit, but this is a serious issue as I'm gearing up to write software to make a "poor man's" network analyzer using a frequency synthesizer and a volt meter, switching between them pretty much as fast as possible. Maybe I'll just use that NI card ;-)
-Bob On Mon, Jul 6, 2009 at 11:07 AM, Samuel D. [x86/CPC] <[email protected]>wrote: > Damn, that's a big flaw. > > The software I'm working on send three "++addr" commands per second. > > Only 4 days @24h/day to reach the limit :-/ > > > -----Message d'origine----- > De : [email protected] [mailto:[email protected]] De la > part de Mark Sims > Envoyé : lundi 6 juillet 2009 18:54 > À : [email protected] > Objet : [time-nuts] Prologix GPIB-USB vs. GPIB-LAN vs. NI was: AW: Prologix > GPIB-USB vs. GPIB-LAN > > > The Prologix adapter has a ++addr command for changing the GPIB address. > You can select different instruments that way. > > Unfortunately, the version I looked seems to have a potentially fatal flaw. > When you change the ++addr, the device writes the internal microprocessor > EEPROM. The EEPROM is speced a 1 million write cycles. If you changed > instruments at once a second, in under two weeks the chip could be toast. > My app could have worn out the chip in under a day... > > All this assumes that Prologix did not implement some sort of elaborate > wear > leveling scheme in their software, but I suspect not. They seem to have > intended one to set up the device to talk to one instrument then save that > configuration in the chip. Dynamically hammering the thing to death with > address changes was not the intention of the ++addr command. > > I wound up implementing a GPIB controller (with Prologix emulator) with my > MegaDonkey touch screen LCD controller. It even included a HPGL/PCL > plotter > routine to draw instrument plots on the 160x80 LCD. > > ---------------------------------------- > > > > > > _________________________________________________________________ > Windows Live™ SkyDrive™: Get 25 GB of free online storage. > http://windowslive.com/online/skydrive?ocid=TXT_TAGLM_WL_SD_25GB_062009 > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
