Change device name of a SPK-B bluetooth audio module

I bought theย BLK-MD-SPK-B for the possibility to change the device name with an AT-command. But when I got it hooked up UART it turned out that the change name command did not work. Bad luck.

The way to change the name was to burn it in to the configuration in the EEPROM-chip:

First you must solder the tiny chip off the board, use tweezers to lift it from the board when you warm up pins.

EEPROM chip soldered off

Tiny EEPROM chip soldered off

Hook theย chip up to an EEPROM programmer.

EEPROM hooked up

Read the data from the chip and save a backup to a file. Then locate the device name.

eepromdump

Replace the old name (in my case “BT-Speaker”) with the name you want for the device (I renamed mine to “Marsboer”) and then write it to the chip.

Yay!

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24 Responses to Change device name of a SPK-B bluetooth audio module

  1. Morten GH says:

    Hello!
    This is exactly what I’m looking for to customize my DIY BT-speaker ๐Ÿ™‚
    Can you provide more details around how you hooked the chip up to a programmer? Maybe I’m wrong, but your picture only shows a eeprom holder?
    What kind of programmer did you use?

    • oyvind says:

      Hi Morten
      I used a cheap eeprom writer called CH341A [ebay link]. The eeprom holder on the picture is a CNV-SSOP-28 [ebay link]. I also use the CNV-SSOP-28 to hook FTDI chips to breadboards. A cheaper method is to use a PCB-board to hook the eeprom chip to the programmer. [ebay link].

      Be adviced that the pins of the chip is very small, I acually ended up breaking the chip when I tried to solder it back on the BT-module again. Luckily I had dumped the binaries of the chip to a file and I had similar eeprom chips laying around, so i programmed a new chip and soldered it on.

      I hope this was any help. If you need any more info I would be happy to help. I also would love to see some pics of your BT-speaker project.

      • Morten GH says:

        Thank you for your response! I managed to blow up my newly acquired amplifier yesterday, so the project has sadly come to a halt. Will get back to you if I try your method ๐Ÿ™‚

  2. Bob Wheeler says:

    Hi Oyvind,

    I have the same bt audio module and wish to do the same thing you did. I am using mine to interface to my custom built tube amplifier. It works well now but I would rather see something like “Bob’s Really Cool Hi-Fi Tube Amplifier” as opposed to “BT-Speaker” when I hook my phone or ipad up to the device. I guess my question to you is, is there a way you can do this without removing the eeprom from the board? These eyes are getting old! Thanks in advance for any advice you could lend.

    Bob

    • oyvind says:

      Hi Bob!

      The eeprom chip on this board is so tiny that I think the only way is to solder it off the board. I actually ruined one BT module while trying to desolder the eeprom, so I understand why you don’t want to do it.

      What you could do is to choose another bluetooth module with a slightly bigger eeprom chip. For example the “KRC-86B”. Then you can use a SOIC8/SOP8 flash clip (search for “SOIC8 Clip” on ebay) to connect the chip to your programmer without removing it from the board.

    • Malinda says:

      Fidnnig this post. It’s just a big piece of luck for me.

  3. Kok says:

    I bought the KRC-86B V4.0

    And write another name to the eeprom, but after re soldering it to the PCB it appeared that the name was changed back to KRC-86B V4.0

    How could this be possible? And can I avoid this?

    Thanks in advance for your reply =)

    • oyvind says:

      I see, maybe there is some code in the startup section that remanes it to KRC-86B each time the chip gets power. I don’t know the solution for this. Please tell me if you find a solution

    • Rob says:

      Hi Kok, I also tried to program that EEPROM, but when powered up the BT module, the KRC-86B V4.0 name appeared again. I also tried to pull up the write-protect pin of the EEPROM, but it was impossible then to connect the module. Did you find different solutions?

  4. Kok says:

    I used the Eeprom writer in your link, in the post above, the CH341A.
    The Eeprom is the AT24C64A chip, right? At least here I read the KRC-86B V4.0 name with the CH341A Programmer.

    There is another chip with the same pin layout, but there is no info/name printed on this chip. Could this also be an Eeprom chip?

    Anyway I also checked the CSR8630 bluetooth chip on the internet and in the info I read this has also “Internal ROM, serial flash memory and EEPROM
    interfaces”…maybe it’s not possible to change the name in this device?

    • oyvind says:

      Thats correct, the EEprom is the AT24C64A chip. It’s not likely that the other chip is a EEprom chip.

      Hopefully you will be able to find the BT-name in clear text in the CSR8630, but I don’t know for sure.

  5. Joris says:

    Why you don’t let me post a reply on this matter? It is usefull information…

  6. Jean-Luc says:

    Hello,

    Thank you for the post, nice job.

    I have diffents BT modules one is nearly the same OVC3868
    But the Eeprom’is 24C08c ? I it the same ?
    And a BT USB module with “Line” L24C32TI that look also very similar.
    I was wondering if they will work ?

    And also the ebay link show a module with a support board included (for soldering the eeprom on it) so no need to buy an extra one ?

    Thanks for your answear.

    • oyvind says:

      Hi Jean-Luc

      I don’t know for sure, but I guess you can find the BT device name in clear text in the eeprom of the chips you mentioned too. Please reply if you can do it.
      I’m sorry but I dont understand what you are asking in your 2. question.

      Hope this helps in any way!

  7. Marek says:

    Hello Oyvind !
    thank you for your time, great work and information

    i have KRC-86B V4.0 with AT24C64A chip.
    Name “KRC-86B V4.0” is in chip twice.

    Test1: If I change name to “KRC-86B TEST” at one place only (first or second place), name will be automatic change to “KRC-86B V4.0” after reboot.

    Test2: If I change name to “KRC-86B TEST” at both locations stop working after reboot (no blinking blue diode port) and chip must me restore from “original.bin”

    Can you help me with some idea ?
    P.S. change name from “KRC-86B V4.0” to “KRC-86B V5.0” is the same situation ๐Ÿ™

    Kindly Regards and thanks again !
    Marek

    Source:
    Orginal ROM: http://burkon.cz/bluetooth/original.bin
    Test1: ROM: http://burkon.cz/bluetooth/restore_name_after_reboot.bin
    Test2: ROM: http://burkon.cz/bluetooth/not_working.bin

    • oyvind says:

      Hi
      I guess my BLK-MD-SPK-B was an early version, because I hear multiple people having trouble with it beeing renamed to the original name again. I’m afraid I don’t have any chips to test with at the moment. There must be something in the startup code that renames it.

      • Marek says:

        Thank you very much Oyvind. If you send me your address, I give you one . It’s important to me.
        Kindly Regards
        Marek

    • Rob says:

      Hi Marek, I suppose it’s a matter of CRC checksum: if you look at the EEPROM, you will see that at the beginning there are some bites which are not reproduced in the “second half” of the memory. They could be a CRC checksum: I asked to the BT chip company about the used algorithm, but they didn’t reply me back. I’m trying to chech with the standard algorithms at the moment, but nothing found yet.

    • Tomas says:

      Eeprom protect cks ๐Ÿ™‚
      use spi programer and crs config tool.

  8. DAVID says:

    Any further progress on this one? Thanks

    • oyvind says:

      I’m sorry, I don’t have time to play with this anytime soon. If you find anything cool, please tell me ๐Ÿ™‚

  9. Jake Little says:

    Hello,
    I haven’t tried this myself, but this:
    https://www.tinyosshop.com/index.php?route=information/news&news_id=42
    …link has a tutorial for programming the crs chip through spi programming.

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