• TI Thinks Resolved

DLPC910: ECP2_FINISHED signal cann't go high (ECP2_FINISHED信号无法拉高)

Prodigy 35 points

Replies: 6

Views: 116

Part Number: DLPC910

The connection between DLPC910 and DLPR910 is referred to TI DLPR910 datasheet. Now, the ECP2_FINISHED signal cann't go high , which means the program cann't be loaded.

The difference with datasheet is that the DLPC910's 50MHz clock is not driven by crystal. The FPGA supplys the 50MHz clock. Therefor, when the DLPC910 load the program, the 50MHz clock is not ready. 

Does this difference matters?

And  how to deal with the ECP2_FINISHED signal cann't go high ?

  • Hello User,

    The APPS_FPGA or your front end should hold the DLPC900 in reset until it is up and sending training patterns.  If it does not, it will not finish initialization correctly.

    It is very much like the DLPC410 in this.  If you have a D4100 EVM you will notice that the DLPC410 indicator starts red then briefly turns green then red and finally green.  This is because once the APPS_FPGA starts running, the first thing it does is reset the DLPC410. 

    The DLPC910 requires this same sequence to initialize correctly.  Since you are feeding the DLPC910 from the FPGA rather than crystal, you may need to add a delay after the FPGA starts sending the 50 MHz clock to the DLPC910 before pulling the DLPC910 into reset.

    Fizix

  • In reply to Fizix:

    Thanks for your answer. The DLPC910's reset is also supplied by FPGA, so before FPGA loads it's program, the 50MHz and reset signal are not ready.

    Therefore, I try to reset the DLPC910 manually after the FPGA program is loaded, and at this situation, the 50MHz clock is ready. However,  ECP2_FINISHED signal is still low.

  • In reply to user6376741:

    Hello again User,

    The training patterns should continue to run until the DLPC910 reports that it is finished.  Does your system run these patterns until ECP2_FINISED goes high?

    Fizix

  • In reply to Fizix:

    hello,

    thank you for your advice. The training pattern is sent to DLPC910 before it's initialization completed.

    Now, the ECP signal can go high(because of the JTAG chain). And VLED0 has the heart beat signal. However, the VLED1 cann't go high. And DLPC910's I2C has no ack when I try to access it using I2C interface.

    So, can you help me to solve this problem?

  • In reply to user6376741:

    Hello again user,

    From your description it sounds like this is a board you have designed and written your own front end FPGA or other code that is now able to get a heartbeat, but is not able to communicate over I2C.  What I2C address are you writing to?

    Fizix

  • In reply to Fizix:

    Hello again user,

    Do you still need assisatnce with this question?  If not could you let us know how you solved it so others can benefit from your learning?

    Fizix