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Measurement of USB eye diagram

Dear All : 

I need to measure the eye diagram on C5535 platform. (USB 2.0)

I found the TESTMODE register in C5535 spec. 

And I want to test the TEST_PACKET mode. 

Can anyone tell me what is the 53-byte data???

  • As stated in the description section, this test package is defined by USB Specification 2.0. If you refer to the USB 2.0 Specification, it is documented in section 7.1.20.

    Regards.

  • As I read your posting further, I might not have answered you posting. Have you been able to scope the package sent by this mode? At the mean time, I will ask among my colleagues for more information.

    Regards.

  • You can use below test packet for USB eye diagram verification. You need to load this into EP0 FIFO and enable TEST_PACKET bit. USB controller will take care of sending data on the bus continuously.

    {0x0000, 0x0000, 0x0000, 0x0000, 0xAA00, 0xAAAA,

    0xAAAA, 0xAAAA, 0xEEAA, 0xEEEE, 0xEEEE, 0xEEEE,

    0xFEEE, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF,

    0x7FFF, 0xDFBF, 0xF7EF, 0xFDFB, 0x7EFC, 0xDFBF,

    0xF7EF, 0xFDFB, 0x007E};

    - Pratap