Empathy List Archives

DC

David C. Partridge

Tue, Jan 3, 2012 8:36 AM

On 22 December I received an email from a Solartron (Ametek) engineer (one of the very few remaining) who had found my web site.

Amongst other things he said:

==== QUOTE ====
Incidentally did you know that the 7081 and 7071 are essentially the same instrument? The reference zener diodes were soaked for several weeks in an oven which temperature cycled them and each diode was checked regularly for stability. The very best ones were selected to go in the tighter specified 7081. The not so good ones went in the 7071. Otherwise the only difference is the front panel and the contents of the EPROMS. The 7081 has an 8 x nines (51 seconds integration time) button. On the 7071 this button is not present and the firmware limits the integration time to 3.2 seconds (7 x nines display). Both units can go down to 3 nines (1.56mS integration time, 100 readings/second) when under remote control although of course this rather defeats the object of having such an long scale instrument.

Out of interest I just took the lid off my 7081 (serial 104) to see what firmware it has in it. The EPROMS which are labelled issue (DD) have the same checksums as in your article and looking at records this seems to be the last version produced. The only difference is that mine are 2764 rather than the 2564 in yours. (They are of course interchangable).
==== END QUOTE ====

It's nice to have confirmation of my suspicion that the ROM set I have IS the final revision.

Cheers
Dave

On 22 December I received an email from a Solartron (Ametek) engineer (one of the very few remaining) who had found my web site. Amongst other things he said: ==== QUOTE ==== Incidentally did you know that the 7081 and 7071 are essentially the same instrument? The reference zener diodes were soaked for several weeks in an oven which temperature cycled them and each diode was checked regularly for stability. The very best ones were selected to go in the tighter specified 7081. The not so good ones went in the 7071. Otherwise the only difference is the front panel and the contents of the EPROMS. The 7081 has an 8 x nines (51 seconds integration time) button. On the 7071 this button is not present and the firmware limits the integration time to 3.2 seconds (7 x nines display). Both units can go down to 3 nines (1.56mS integration time, 100 readings/second) when under remote control although of course this rather defeats the object of having such an long scale instrument. Out of interest I just took the lid off my 7081 (serial 104) to see what firmware it has in it. The EPROMS which are labelled issue (DD) have the same checksums as in your article and looking at records this seems to be the last version produced. The only difference is that mine are 2764 rather than the 2564 in yours. (They are of course interchangable). ==== END QUOTE ==== It's nice to have confirmation of my suspicion that the ROM set I have IS the final revision. Cheers Dave

JL

J. L. Trantham

Tue, Jan 3, 2012 1:46 PM

Dave,

Do you recall the information you receive from your 7081 when you connect to
the meter via an RS232 terminal and (IIRC) hit 'Initialise'? Mine says:

VDD BSW 8 De 86 8 50

Mine is SN 001523 and also has 'DD' labeled EPROM's. Therefore, I wonder if
the 'VDD' statement reflects version DD of the firmware?

BTW, the calibration on my meter was done by Dave Moon.

Joe

-----Original Message-----
From: volt-nuts-bounces@febo.com [mailto:volt-nuts-bounces@febo.com] On
Behalf Of David C. Partridge
Sent: Tuesday, January 03, 2012 2:36 AM
To: 'Discussion of precise voltage measurement'
Subject: [volt-nuts] Solartron 7081 ROM images

On 22 December I received an email from a Solartron (Ametek) engineer (one
of the very few remaining) who had found my web site.

Amongst other things he said:

==== QUOTE ====
Incidentally did you know that the 7081 and 7071 are essentially the same
instrument? The reference zener diodes were soaked for several weeks in an
oven which temperature cycled them and each diode was checked regularly for
stability. The very best ones were selected to go in the tighter specified
7081. The not so good ones went in the 7071. Otherwise the only difference
is the front panel and the contents of the EPROMS. The 7081 has an 8 x nines
(51 seconds integration time) button. On the 7071 this button is not present
and the firmware limits the integration time to 3.2 seconds (7 x nines
display). Both units can go down to 3 nines (1.56mS integration time, 100
readings/second) when under remote control although of course this rather
defeats the object of having such an long scale instrument.

Out of interest I just took the lid off my 7081 (serial 104) to see what
firmware it has in it. The EPROMS which are labelled issue (DD) have the
same checksums as in your article and looking at records this seems to be
the last version produced. The only difference is that mine are 2764 rather
than the 2564 in yours. (They are of course interchangable).
==== END QUOTE ====

It's nice to have confirmation of my suspicion that the ROM set I have IS
the final revision.

Cheers
Dave

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Dave, Do you recall the information you receive from your 7081 when you connect to the meter via an RS232 terminal and (IIRC) hit 'Initialise'? Mine says: VDD BSW 8 De 86 8 50 Mine is SN 001523 and also has 'DD' labeled EPROM's. Therefore, I wonder if the 'VDD' statement reflects version DD of the firmware? BTW, the calibration on my meter was done by Dave Moon. Joe -----Original Message----- From: volt-nuts-bounces@febo.com [mailto:volt-nuts-bounces@febo.com] On Behalf Of David C. Partridge Sent: Tuesday, January 03, 2012 2:36 AM To: 'Discussion of precise voltage measurement' Subject: [volt-nuts] Solartron 7081 ROM images On 22 December I received an email from a Solartron (Ametek) engineer (one of the very few remaining) who had found my web site. Amongst other things he said: ==== QUOTE ==== Incidentally did you know that the 7081 and 7071 are essentially the same instrument? The reference zener diodes were soaked for several weeks in an oven which temperature cycled them and each diode was checked regularly for stability. The very best ones were selected to go in the tighter specified 7081. The not so good ones went in the 7071. Otherwise the only difference is the front panel and the contents of the EPROMS. The 7081 has an 8 x nines (51 seconds integration time) button. On the 7071 this button is not present and the firmware limits the integration time to 3.2 seconds (7 x nines display). Both units can go down to 3 nines (1.56mS integration time, 100 readings/second) when under remote control although of course this rather defeats the object of having such an long scale instrument. Out of interest I just took the lid off my 7081 (serial 104) to see what firmware it has in it. The EPROMS which are labelled issue (DD) have the same checksums as in your article and looking at records this seems to be the last version produced. The only difference is that mine are 2764 rather than the 2564 in yours. (They are of course interchangable). ==== END QUOTE ==== It's nice to have confirmation of my suspicion that the ROM set I have IS the final revision. Cheers Dave _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.

Михаил

Tue, Jan 3, 2012 4:51 PM

Hi, David!
Solartron (Ametek) engineer not right. 2564 and 2764 EPROMs are not
interchangable due to pinout differences.
I have a very old 7081 (#231) with both ROM-sets dated 1984. After about three
months of exploring now I'm trying to write an article about Solartron 7081
internal features, bugs and workarounds. But it not easy for me.
The day before New Year, I'm found a solution for the 7081 drift correction
errata. This errata is related to Floating Logic firmware, located in the IC803.
IC803 ROM firmware is more critical than Earthy Processors ROM-set, because it
contains all of the hardware-specific delays, registers look-up tables,
two complicated finite-state machines, virtual timers, software GLUGs
integrator, interboard messagind system interface e.t.c. If you are interested
in, the solution in this file: http://www.fileserve.com/file/wntURSH/Patch_ic803.rar

Mickle T.

Tuesday, January 3, 2012, 12:36:10 PM, you wrote:
DCP> On 22 December I received an email from a Solartron (Ametek) engineer (one
DCP> of the very few remaining) who had found my web site.

DCP> Amongst other things he said:

DCP> ==== QUOTE ====
DCP> Incidentally did you know that the 7081 and 7071 are essentially the same
DCP> instrument? The reference zener diodes were soaked for several weeks in an
DCP> oven which temperature cycled them and each diode was checked regularly for
DCP> stability. The very best ones were selected to go in the tighter specified
DCP> 7081. The not so good ones went in the 7071. Otherwise the only difference
DCP> is the front panel and the contents of the EPROMS. The 7081 has an 8 x
DCP> nines (51 seconds integration time) button. On the 7071 this button is not
DCP> present and the firmware limits the integration time to 3.2 seconds (7 x
DCP> nines display). Both units can go down to 3 nines (1.56mS integration time,
DCP> 100 readings/second) when under remote control although of course this
DCP> rather defeats the object of having such an long scale instrument.

DCP> Out of interest I just took the lid off my 7081 (serial 104) to see what
DCP> firmware it has in it. The EPROMS which are labelled issue (DD) have the
DCP> same checksums as in your article and looking at records this seems to be
DCP> the last version produced. The only difference is that mine are 2764 rather
DCP> than the 2564 in yours. (They are of course interchangable).
DCP> ==== END QUOTE ====

DCP> It's nice to have confirmation of my suspicion that the ROM set I have IS the final revision.

DCP> Cheers
DCP> Dave

Hi, David! Solartron (Ametek) engineer not right. 2564 and 2764 EPROMs are not interchangable due to pinout differences. I have a very old 7081 (#231) with both ROM-sets dated 1984. After about three months of exploring now I'm trying to write an article about Solartron 7081 internal features, bugs and workarounds. But it not easy for me. The day before New Year, I'm found a solution for the 7081 drift correction errata. This errata is related to Floating Logic firmware, located in the IC803. IC803 ROM firmware is more critical than Earthy Processors ROM-set, because it contains all of the hardware-specific delays, registers look-up tables, two complicated finite-state machines, virtual timers, software GLUGs integrator, interboard messagind system interface e.t.c. If you are interested in, the solution in this file: http://www.fileserve.com/file/wntURSH/Patch_ic803.rar Mickle T. Tuesday, January 3, 2012, 12:36:10 PM, you wrote: DCP> On 22 December I received an email from a Solartron (Ametek) engineer (one DCP> of the very few remaining) who had found my web site. DCP> Amongst other things he said: DCP> ==== QUOTE ==== DCP> Incidentally did you know that the 7081 and 7071 are essentially the same DCP> instrument? The reference zener diodes were soaked for several weeks in an DCP> oven which temperature cycled them and each diode was checked regularly for DCP> stability. The very best ones were selected to go in the tighter specified DCP> 7081. The not so good ones went in the 7071. Otherwise the only difference DCP> is the front panel and the contents of the EPROMS. The 7081 has an 8 x DCP> nines (51 seconds integration time) button. On the 7071 this button is not DCP> present and the firmware limits the integration time to 3.2 seconds (7 x DCP> nines display). Both units can go down to 3 nines (1.56mS integration time, DCP> 100 readings/second) when under remote control although of course this DCP> rather defeats the object of having such an long scale instrument. DCP> Out of interest I just took the lid off my 7081 (serial 104) to see what DCP> firmware it has in it. The EPROMS which are labelled issue (DD) have the DCP> same checksums as in your article and looking at records this seems to be DCP> the last version produced. The only difference is that mine are 2764 rather DCP> than the 2564 in yours. (They are of course interchangable). DCP> ==== END QUOTE ==== DCP> It's nice to have confirmation of my suspicion that the ROM set I have IS the final revision. DCP> Cheers DCP> Dave

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Solartron 7081 ROM images