Need help on CRC module

Hello Tim,

I have forwarded your request on one of the experts, who can assist with this code example.

Best regards,
TI Hercules Forum Support

Hi Diwakar,

    OK! Thanks a lot for your quickly response!

Tim Park

Hi Zhaohong,

     Thanks a lot for your reply! I don't have much experience with Hercules. So I still need your help. Which device doed the example base on ?  Would you please post the entire project file? Thanks again!

  Regards,

  Tim

Tim,

Those examples apply for all TI Cortex R4 based device with DMA support. CRC channel 0 is configured for full cpu and semi cpu mode. channel1 is configured for auto mode. In our test, auto mode is triggered by call CRC1_Start() form a RTI ISR. An CRC interrupt will occur if there is an error. The examples are pulled off from a big CCS3.3 project for silicon validation. The project is not compatible with CCS 5. I would suggest you starting a CCS5 using the halcogen tool. Then you can use those source code if you want.

Thanks and regards,

Zhaohong

Hi Zhaohong,

      Thank you very much for your help! But the TRM is short on detail and I'm sill confused with Hercules CRC module .  I can't run your codes or  use  Halcogen to implement these functions.  Could you please spend some time helping me to creat a project through CCS V5 to realize CRC function through different CRC modes? Thanks in advance！！

Regards，

Tim

Hi all,

       Could someone help me with this issue?  Thanks a lot in advance!

  Regards,

  Tim

Hi Prathap,

     Thanks a lot!

     Up to now, TI hasn't any Hercules ,TI's safet MCU, CRC example within CCS v5  to demonstrate its auto,semi-cpu and full-cpu crc mode?  Looking forward to your early reply!

Regards,

 Tim

Hi Prathap,

    I really appreciate your help.

    I can successfully run the semi-cpu mode example. And then I do a full-cpu mode test based the codes you provided to me, but I can't get the same result as the semi-cpu mode? Could you please help to solve the problem?  My program is as below:

    3010.crc_fullcpu_mode.zip

  Thanks again for you patience.

  Regards!

  Tim

Hi Prahtap,      

Really want to get the help from you.  I first get a result from semi-cpu mode, but I can't get the same result from full-cpu mode. Please find my codes as the attached file in the last post.  Could you please help to check if TI's test team can provide the Full-CPU mode CRC example like the semi-cpu mode mode codes before the weekend? I think it must to be very helpful to developers of safety product based on Hercules. Thanks a lot!

Regards!

Tim

Hi Tim,

Since the writes through DMA is 64bit and through CPU is 32bit you will see difference in the CRC value.
So in your system you must make sure the way you calculate the golden value and compare must match.

Try doing 32bit writes using DMA and this should match the Full CPU method.

Regards
Prathap

Hi Prathap,

     Thanks a lot! Then you mean TMS570LS3137 CRC full CPU mode doesn't support 64 bit data size?

Regards

Tim

Tim,

Full CPU mode supports 64 bit data size. In the example I posted earlier. The CRC value generated by full CPU mode with two 32 bit write matches the one generated by semi CPU mode using 64 bit DMA write. You can also take a look at the attached file for full CPU mode. It use 64 bit wrtie.

7167.crccpu64_EABI.asm

Thanks and regards,

Zhaohong

Another methodology to achieve 64-bit writes in Full CPU mode is to enable the bus monitoring or snooping mode. This way you will not have to perform a read-write using the CPU. Essentially, you read the data and it is automatically copied to the PSA register and included in the CRC calculation.

Hi Zhaohong,

    Thanks for your reply!  I program the full cpu mode codes as your guide, but I get the different results. Please find the semi cpu mode and full cpu mode codes as the attached file. 

 5824.CRC_codes_semi_full_compare.zip 

 Hope you can find the mistake I made. Thanks a lot for you time.!

Regards,

Tim

Hi Chuck,

    That's very cool! Could you pleae help to post the codes? Then we all can learn more about CRC module. Thanks!

Regards,

Tim

Hi All,

     Thanks again for your help!

Regards!

Tim