Fluke 87-V "Err EEpr" MCU (MSP430F448) Programming - Page 1
Forum section: electronics / repair

author: whitepawn
author_rank: Newbie
timestamp: July 24, 2024, 09:28:40 am
content: Hi,A seller locally sells a Fluke 87-V for a reasonable price but he claims that DMM have "Err EEpr" error while powered on. According to similiar below forum posts i read, device MCU should be reprogrammed.https://www.eevblog.com/forum/repair/fluke-117-err-eepr/https://www.eevblog.com/forum/repair/fluke-115-eepr-error-rewriting-msp430f448/I checked service manual and realised 87-V have same MCU which is MSP430F448. PCB have test JTAG test points for programming MCU. The problem is i have experience for Atmel and ST MCU's before but never a TI job. My understanding is i have to get exact MCU (LCSC have this about 2.5USD) desolder it and resolder new MCU. I can manage hardware side (removing MCU-resoldering MCU) without so much hassle.I am aware that firmware is unobtainable from fluke butis it possible to dump an existing multimeter firmware?I know that i have to recalibrate it with "new" firmware but is dumping existing firmware possible on this MCU? or MCU is locked for read like ST MCU's? If its possible to dump firmware which hardware (Like ST's ST-Link) i suppose to use since i am not familiar with TI MCU programming.Any guidance will be appreciated.

author: digger
author_rank: Regular Contributor
timestamp: July 24, 2024, 09:36:57 am
content: how about trying fluke's warranty as a hail mary

author: coromonadalix
author_rank: Super Contributor
timestamp: July 24, 2024, 10:47:43 am
content: even having another meter, it depends if you are able to extract an content OR the mcu is locked from being read ....try the warranty if it is applicable ?

author: shakalnokturn
author_rank: Super Contributor
timestamp: July 24, 2024, 10:55:44 am
content: It's very unlikely that Fluke left the firmware unprotected from read-back, the trend these days is to lock the end user out as much as possible.The flash (firmware itself) is should be OK otherwise the multimeter wouldn't be displaying anything that makes sense.It's possible that the internal EEPROM on the MSP has a hardware fault which would require replacing the MSP of course (and obtaining the firmware to program).Still most likely to me would be "only" corrupt data in the EEPROM (values that are out of range or data structure makes no sense so firmware throws an error).Have you tried accessing calibration menu?

author: whitepawn
author_rank: Newbie
timestamp: July 24, 2024, 11:42:55 am
content: Thanks all for your answers.Quote from: digger on July 24, 2024, 09:36:57 amI am not sure but seller is the "original owner". I will ask him. So if he is not original owner not fluke warranty is not applicable i believe.Quote from: coromonadalix on July 24, 2024, 10:47:43 amMultimeter seems old so maybe warranty period is over i am not sure. DMM can have GSM bug which may lead warranty replacament i am not sure. I can ask seller for board revision but he may not want to open up device.Quote from: shakalnokturn on July 24, 2024, 10:55:44 amI also believe firmware is protected like ST MCU's. I wonder if some known hardware or software vulnerability may MCU have to dump firmware or eeprom data. Some known voltage glitch attack may work also. Since i am not familiar with this type of MCU i am looking for alternatives for dumping fimware.

author: coromonadalix
author_rank: Super Contributor
timestamp: July 24, 2024, 02:02:02 pm
content: you have to read about glitching and or exploits on this mcu, if there anyor as a last resort find a donnor board ?

author: digger
author_rank: Regular Contributor
timestamp: July 26, 2024, 07:33:39 pm
content: who cares who the original owner is, just try it. it's a low effort first attempt at resolving the problem. pretend you're the original owner. no, you don't have your receipt.

author: Ugur
author_rank: Regular Contributor
timestamp: July 29, 2024, 11:23:44 am
content: Don't worry, Fluke 87-V series multimeters have a limited lifetime warranty. That is, it is LLTW.The failure of this processor is not a user error and must be repaired/replaced by an authorized service free of charge.You can review the first page of the user manual.