TDS510A backup EEPROM NVRAM Firmware - Page 1
Forum section: electronics / repair

author: Tantratron
author_rank: Frequent Contributor
timestamp: November 22, 2024, 02:48:54 pm
content: Hello, since end of 2018 I've owned or repaired different TDS500/700/C/D oscilloscopes where I systematically used tektools to save their NVRAM content, their firmware and their acquisition board EEPROM calibration constants. The tektool suite was used sometimes to upgrade the FW or write new NVRAM (i.e. DS1486 and DS1250Y) because it was bricked at boot (NVRAM DS1486 battery failure), same to replace and write new eeprom 24C02 which sometimes fail.For different reasons, I've decided to purchase last june 2023 a TDS510A which runs with 68020 instead of 68040 as the C or D serie. I was able to to tektool dump the firmware and the NVRAM but it is not clear how to do it for EEPROM. The unit was de-assembled to be clean, in fact all the boards are super state with no capacitor plague, obviously tektronix solved the issue by 1999 when the TDS510A was constructed.I've looked on both side of the Acquisition board but I cannot see where are the two I2C memory chips, do you know if the 24C02 were used on the TDS510A and previous TDS (serie A or B) which runs under 68020 ?Thank you, Albert

author: Tantratron
author_rank: Frequent Contributor
timestamp: November 24, 2024, 05:14:05 am
content: I'm attaching two global pictures showing top and bottom of respectively the CPU board (68020) and ACQ board.Does anybody can help me locate where are the acquisition EEPROM memories ?Thank you

author: TERRA Operative
author_rank: Super Contributor
timestamp: November 25, 2024, 12:01:41 am
content: Did this scope have the 'firmface' board that plugged into the Processor board just behind the front control panel? If so, that's where the firmware is stored.Otherwise, it'll either be in some flash chips, or in the NVRAM (probably the ramified timekeeper?) on the Processor board.

author: Tantratron
author_rank: Frequent Contributor
timestamp: November 25, 2024, 05:19:55 am
content: Quote from: TERRA Operative on November 25, 2024, 12:01:41 amI do not understand the meaning or what is "firmface", could you share a picture as an exemple ?

author: Tantratron
author_rank: Frequent Contributor
timestamp: November 25, 2024, 09:44:25 am
content: Ok now l look on ebay with keyword firmface and tektronix, I understand what this is physically => as you saw in my 2nd post with pictures, that is all I have when removing the boards so there is no firmface with this TDS510A.Quote from: TERRA Operative on November 25, 2024, 12:01:41 amCan you detail where these flash chips storing the acquistion board calibrated value can be found in the TDS510A ?Unless do you confirm that initial TDS500/700 serie A, B or no suffix would stored the calibrated value directly in the NVRAM versus later C/D versions stored in two I2C flash chip soldered in the acquisition board ?

author: TERRA Operative
author_rank: Super Contributor
timestamp: November 25, 2024, 11:16:37 am
content: The calibration data is stored in a couple of SOIC-8 EEPROM chips on the acquisition board.Would have to check schematics, but probably around the large chip with the circular heatsink. This way the calibration is tied to and follows the acquisition board where is is needed.Check around there for EEPROM's and they are probably what ypu are looking for.The UVEPROM on the processor board is the bootloader.Unlocked options, saved waveforms, and (I still haven't fully figured this out) firmware is stored in the NVRAM's on boards that don't have flash chips, Ithink....Ibelieveearlier models (i.e. not C and D models etc, maybe more) don't use flash chips, hence the use of a firmface board on some scopes and the NVRAMS for firmware.Again, Ithinkthis is vaguely correct, but I haven't looked deeply into it. There are a lot of processor board variants across the TDS500/600/700 series scopes....To dump the EEPROM cal data, there is a floppy tool to do this somewhere on the forum.

author: Tantratron
author_rank: Frequent Contributor
timestamp: November 26, 2024, 05:17:31 am
content: Please read my first post, I know where are the two SOIC-8 EEPROM on any TDS500/700/B/C and I've read/written these with tektools or floppy disk many times.My problem and question, where are these flash chip EEPROM on the TDS510A since I see no firmface ?

author: picburner
author_rank: Frequent Contributor
timestamp: November 26, 2024, 06:44:28 am
content: This particular scope does not have the calibration constants placed in eeprom like the subsequent scopes of the TDS xxx family.In fact it does not have the eeprom on the acquisition board.If you read the service manual on page 5-2 it is explicitly stated that the adjustment constants are placed in the NVRAM.

author: Tantratron
author_rank: Frequent Contributor
timestamp: November 26, 2024, 10:40:58 am
content: Quote from: picburner on November 26, 2024, 06:44:28 amThank you to confirm what i've thought initially after looking everywhere on the boards. So I guess this explains why the GPIB (tektools or getcaldata) or floppy method would not work to recover any ACQ calibration data. I was only able to dump the NVRAM and the firmware for safety reasons in case the NVRAM's internal baterries would fail.