Looking for Mr. David Smith. Was: Expiring EPROM's inHP's?


Dear Community,

I've read the message: "Expiring EPROM's inHP's?" Posted by Marta on 14 Apr 2006, 7:58 a.m.

and the answer of David Smith: Posted by David Smith on 15 Apr 2006, 2:28 p.m.,in response to message #1 by Marta

>... I have experienced quite a bit of problems with data stored in MCM2801 EEPROMs used as configuration parameter storage in Mettler PE series scales. These were first gen EEPROMS and are now leaking their bits. Whenever I restore one of these scales, I rewrite them....>

I've got such a scale, the MCM2801 is dead (or has forgotten all his informations) and I want to rewrite this EEPROM, but I don't have any informations, what my PE6000 wants to have in that memory. If you read that, Mister Smith, give me a hint. I would be very happy, cause I'm running at this balance since serveral years to cure it!

Thank You!

Wolfgang (from Germany)


I just got in a PE6000 and will dump it's memory shortly. Your problem could also be due to bad power supply filter capacitors. The PE series (and frankly ALL older Mettler and Sartorius scales) need their filter caps replaced.

Also do you have the ability to program the MCM2801? I do not know of any device programmer that supports it (or the SDA2006 used in the Sartorius MP8 series of scales).


Hello David,

I'm very, very happy, that you are obviously relativly active in this message board :-))).

The PE6000, I mentioned, display's only "error". I don't have any service manuals, so I replaced the MCM2801 and hoped, that the balance does init the memory for itself, when there is a complete empty storage.... no way...

Do you think, the filtering capacitors could produce a similar message? My "feeling" says, that the weighting cell (and thefore the analog circuits)is working ok (the "pendulum" stays in the middle of the "power-compensation-coil", independent whether you apply less or more force to the weighting table.

If I could receice the dumpvalues of the 16x 16bits from you, that are stored typically in that memory, I would build a writing circuit for the MCM2801. The datasheets are easy available and it don't looks like whitchwork. Ok, it would be some work, but I like Mettler balances and my old PM4600 remained at my divorced wife, so I need a new one...

If you got the possiblity, to rewrite the EEPROMS easier, I could also imagine, that I send you my two MCM's and you rewrite them for me. Naturally, I would pay your work and backshipping costs..

At last, one more thougt. One guy of mettler, I talked to before years, mentioned, that after each repair of the analog circuit these balances had to be "reinitalized". Perhaps there is a testpoint, which is measured with the internal A/D-converter to indicate an "error" in the analog board. In this case, the data from a other PE-6000 wouldn't help, or only by random???

Is it ok, to post such long "off topic" text's here or should we communicate per mail? Me mail address would be Thomas.WolfgangAT

Best regards



Yes, bad filter capacitors can easily cause the "Error" message. They need to be replaced no matter what. I would replace them before building a EEPROM writer. But the EEPROMS will eventually lose data and need to be reprogrammed anyway. The EEPROM tells the microprocessor what type of machine it is. I don't think there is a way of telling the microprocessor how to initialize the EEPROM for a particular type of machine.

As far as reinitializing the scales, he was probably referring to adjusting the various pots (variable resistors) in the machines. They control the linearity, temperature compensation, and zero drift compensation. Go to www.iescorp.com and download their field service handbook (http://iescorp.com/handbook.htm ) for everything you would ever want to know about balances. I have found these adjustments need to be done on all older machines. The temperature compensation proceedure is very tedious and can take over a week to do. Also the cornerload will probably need adjustment.

Here are the values found in my Mettler EEPROMS:

PE360        PE3600      PE6000    PE16
00D0 0001 00D0 0001
0080 0080 0080 0080
4064 CFBD B26E 30DF
D037 E936 810A 8517
EE80 EE80 EB92 543D
0736 0736 2608 0317
0000 0000 0000 0000
0000 0000 0000 0000
0000 0000 0000 0000
0000 0000 0000 0000
0211 0305 042C 0421
3500 3500 7100 E200
D00C D00C 1002 D004
2BF4 2BF4 0775 138A
5300 5300 FFF8 FFF8
0E07 1907 067F BD7F

Edited: 9 Sept 2006, 8:12 p.m.

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