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QN908x Enhanced image bricks device

Question asked by Jose Raffucci on Feb 19, 2018
Latest reply on Feb 23, 2018 by Gerardo Rodríguez

This issue is related to this thread I started about ISP in general - QN908X ISP HOWTO?.  I am currently trying to figure out why my chip does not go into ISP USB mode.

 

I have a QN908C on a custom board.  I am able to create an image in IAR an flash via jflash successfully.  I can also take this image, create a legacy image and also successfully flash to my device in the same manner. 

 

When I try to create a USB image however, jflash complains that:

  1. The CRC is incorrect
  2. The CRP function is not supported in the device type.

 

Neither of these appear to be an issue when the non-crp  NXP QN9080C device is selected in jflash.

 

USB image is generated by the command

N908x_Image_Editor_v1.0.0.exe -i <file.bin> -u

 

JFlash generates its own CRC (red).  The CRP register is unchanged from the default (0x0aa8ff).

 

 

I get these errors and the unit flashes successfully and my app runs but I am unable to get it to boot into ISP mode.

 

(Yes to CRC)

 

I tried again with the CRP enabled device.  The image flashes but I lost the connection, I am unable to talk to it again via SWD.  It also does not respond to the CHIP_MODE pin.  After I attempted to flash, I noticed that the CRP bits are different:

 

 

I'm guessing that my devices are not recoverable at this point, right?

 

Why is the image different between the two devices and why is the Image editor not generating a valid CRC?

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