USBBulkSourceSink stop working after add uart print in Dma Callback

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xixu_4093676
Level 3
Level 3
25 replies posted 10 replies posted 10 questions asked

Hello support,

I try to add  "CyU3PDebugPrint (4, "CyU3PDmaChannelGetBuffer buf_p.size %d\n", buf_p.size);" into CyFxBulkSrcSinkDmaCallback (cyfxbulksrcsink.c  line 227).

then streamer tools can not get data from IN endpoint.

By My understand, it maybe get very slow transfer data speed.

Can you let me know what is reason on the issues?

for your reference, I also attach my modified code on the offical sample code USBBulkSourceSink.

Thanks,

Martin

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JayakrishnaT_76
Moderator
Moderator
Moderator
First question asked 1000 replies posted 750 replies posted

Hello,

It is not recommended to use the API CyU3PDebugPrint() inside a callback function. This is because it will delay the processing of DMA interrupts on all channels in the system. This is documented in page 46 of the document Getting started with FX3 SDK which can be found in the following location:

C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\doc\firmware

Note: This path may change depending on the installation directory of FX3 SDK.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna

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1 Reply
JayakrishnaT_76
Moderator
Moderator
Moderator
First question asked 1000 replies posted 750 replies posted

Hello,

It is not recommended to use the API CyU3PDebugPrint() inside a callback function. This is because it will delay the processing of DMA interrupts on all channels in the system. This is documented in page 46 of the document Getting started with FX3 SDK which can be found in the following location:

C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\doc\firmware

Note: This path may change depending on the installation directory of FX3 SDK.

Best Regards,

Jayakrishna

Best Regards,
Jayakrishna
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