My K20 chip does not work out

[songtao8940]

hi，I use the K20, when I weld the board found that the chip is locked, according to the Internet after unlocking unlock K60, pin level can vary, but can not communicate, both bus 485 and can not work, I I would like to ask why this is

[kerryzhou]

Hi,

    What the solider temperature you are using? From the K20 datasheet, you can get that the solider temperature should below 260°C.

  Now, do you have the Segger Jlink? You can use the JLINK commander to check, whether you can find the ARM cortex M4 core? If the core can't be found, the chip may be damaged by your solider.

Have a great day,
Jingjing

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[songtao8940]

hi,

    very thanks，that's exactly what I want to know

[kerryzhou · Accepted solution]

If this post answers your question, please click the Correct Answer button. Thank you!

Jingjing