TMS320F28375D: USB triggering for loading data via DMA

Hi Lenio,

We currently do not have any examples for this.

We have a plan to develop some USB with DMA examples in the future. We hope to release something probably around 2Q 2019.

sal

Hi Lenio,

There is a hardware bug with the DMA hook-up to USB FIFO. However, using DMA should still be possible with the below software workaround.

You will have to place the DMA in one-shot mode. And then on a completed transfer (perhaps in the DMA complete ISR) you will have to re-enable the DMA for one shot mode.

You should be able to use either SW triggering or some hardware peripheral triggering like usual.

Hope this is helpful.

Regards,
sal

Hi Lenio,

There may be other ways to do this, than what I describe below. We have not implement this yet, so I can only offer suggestions/thoughts.

Once data is received a USB interrupt is triggered. From the USB library call back function, the DMA could be triggered via forcing it with SW after first reading how many bytes are available. Then the library or the DMA completion ISR could modify the USB buffers to specify the data has been read.

Again, we have not implemented this yet, so I cannot be that helpful with regard to much more detail.

Regards,
sal

Hi Lenio,

These event triggers correspond to the interrupt status bits in the USBTXIS and USBRXIS registers.

Regards,
sal