topic Re: Loking for an RT105x spi double buffer example in i.MX Processors

Looking for an RT105x spi double buffer example

ryanshuttlewort — Tue, 16 Jan 2018 18:10:56 GMT

Hello, I am using IAR with an RT1050 SDK, version 2.3.0 (2017-11-16). I have been looking through various eDMA examples but nothing quite fits what I am trying to achieve. I am looking for an example of continuously reading the lpspi RX register via. DMA, triggered when the FIFO hits a given watermark. I then want the DMA to populate one buffer with this data until full, then switch to another and back again and so on, issuing an ISR on the filling of each buffer. I would call this double buffering but I have seen it referred to as a ping-pong setup. I have seen examples for other processors but I am looking for an RT105x specific example, perhaps an i.MX example would also suffice given the similarities.

Thanks, no RTFM responses please.

Re: Loking for an RT105x spi double buffer example

weidong_sun — Wed, 17 Jan 2018 04:26:08 GMT

Helo Ryan,

We didn't provide example code on double buffer & eDMA transfer based on LPSPI. Suggest you can refer to routine of

scatter_gather in eDMA, trying to do it by yourself.

Have a great day,
TIC Weidong Sun

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Re: Loking for an RT105x spi double buffer example

ryanshuttlewort — Wed, 17 Jan 2018 15:40:24 GMT

For anyone else looking for a similar solution, this link provides some insight into the TCD setup.