Keithley 2015 THD no audio signal (FPGA hangs when reading the configuration) - Page 1
Forum section: electronics / testgear

author: diodak
author_rank: Regular Contributor
timestamp: October 19, 2016, 06:54:59 pm
content: I bought a broken multimeter Keithley 2015 THD. The problem is the lack of a signal at the output of the generator. After many tests I have established as follows:1. Sometimes FPGA U334 (XC5202) does not read the entire configuration (only part). Then there is a low level on the TL7705 pin 5 (U345).2. When the configuration is downloaded, there is no control AD9850 (U301 - pins 7,8,9). There are only control signals for DAC MAX543 (U334 - pins 3,4 and 5).3. Optocouplers U320,321 and 324 transmit data to the FPGA.4. The power supply voltages are correct (+ 5V, + 15V and -15V) and without noise.5. FPGA probably only redirects the signals from the optocouplers (clock on pin 5 MAX543 is the same as for the U320 -a part of the pulses is in the reverse phase)What could be the reason?I would like to eliminate damage to the FPGA U334. Is a good idea to re-upload the configuration to AT17LV65 (U346 - marked "2015 808A02")?Whether the contents of the memory may have been damaged? XC5202 has algorithms to verify the configuration data.However, they relate only to the transmission of serial data (not sure).Can someone download a memory contents from U346?Below example when loading of the configuration was stopped (channel 3 - clk, 5 - reset (pin 5 TL7705) and 7 - data from AT17LV65) . What else I stated: no drive relay (setting output impedance 600 / 50R).

author: diodak
author_rank: Regular Contributor
timestamp: October 29, 2016, 07:59:47 pm
content: I checked the readout memory by programmer. Each reading is different. It is not possible to program it (or reset). Therefore, it is clearly the fault memory.I am repeating my request - has anyone dump file U346?

author: MadTux
author_rank: Frequent Contributor
timestamp: October 30, 2016, 11:00:28 am
content: How do I read U346?Are 24Cxx EEPROMs compatible to AT17LV65? Which one?I currently have a 2015 in parts to change caps, so I can do that easily.

author: diodak
author_rank: Regular Contributor
timestamp: October 30, 2016, 06:43:30 pm
content: The only (known to me) way of reading these memories is to use the programmer from this link:www.atmel.com/Images/doc0642.pdfIt works only on WIN XP and uses LPT port. In return, it is very easy to build...Maybe other work, but for me it was easier to make a programmer on a universal PCB.

author: MadTux
author_rank: Frequent Contributor
timestamp: October 30, 2016, 11:11:29 pm
content: That is much to complicated for me.But if you want, I'll remove these four 17AT65 chips from my 2015 and ship them to you.Then you can dump/copy and send them back afterwards.Please upload the images here for everyone.PM me your address and I'll ship them

author: diodak
author_rank: Regular Contributor
timestamp: October 31, 2016, 08:53:05 am
content: I do not know whether it is safe to send memory (if only because of the X-ray scan). I send a programmer I've ever made. Just like I said you need a computer with a LPT port and 2000 / XP system.

author: MadTux
author_rank: Frequent Contributor
timestamp: October 31, 2016, 11:26:25 am
content: I can also do that, I have a few old XP machines with LPT port.But shipping these chips is probably simpler and cheaper (fits into small letter).Never had problems shipping instruments with memory in it around the world.#1 killer of all kind of flash/EPROM is age, IMO, (hard) X-rays aren't that harmful because they mostly penetrate the object without much interaction/ionisation.

author: MadTux
author_rank: Frequent Contributor
timestamp: November 08, 2016, 01:07:18 pm
content: Received the 17AT65 programmer from diodak today.Programmer works great, thank youDumped and verified all 3 17AT65s and added the latest K2015-B17 firmware, so the content of every K2015 EEPROM is backed up now. Maybe someone could upload it to TiN website? I will also upload to ko4bb.

author: diodak
author_rank: Regular Contributor
timestamp: November 08, 2016, 07:24:43 pm
content: Great newsI'll verify data with my memories. When I get new 17AT65, I'll try to upload and see what happensThank you for your help so far.

author: diodak
author_rank: Regular Contributor
timestamp: December 10, 2016, 05:13:48 pm
content: I received AT17LV65. I programmed them ... and generator aliveJust in case I have a stock of 2 pieces of memory for the rest of the FPGA. I suppose I'll have to make internal calibration. The serial numbers on the PCB DMM are different on the label and the other stored in the EEPROM. This is the risk of purchasing faulty equipment. But that's a topic for another thread ...

author: bozidarms
author_rank: Regular Contributor
timestamp: December 11, 2016, 06:08:57 pm
content: What a great collaboration - Spirit in this blog is simply unbeatable,hats offRegards