topic Using eMIOS as a hardware trigger for SDADC in MPC5xxx

Using eMIOS as a hardware trigger for SDADC

erickarr — Wed, 24 Jan 2018 17:49:51 GMT

I am using the MPC5746R to collect data samples from the SDADC. Currently I am using a DMA transfer to remove conversion results from the data queue. If I wanted to employ a hardware trigger with the eMIOS, how would I go about doing so?

I have reviewed the 'Input Muxing' sheet in the 'IO_Signal_Description_and_Input_Multiplexing_Tables.xlsx', and found that the corresponding MSCR register is 970, for the Start Trigger mechanism. But I cannot find any mapping between this input and the eMIOS pins. I would like to also implement the DMA enable gate.

Thanks,

Eric

Re: Using eMIOS as a hardware trigger for SDADC

davidtosenovjan — Thu, 25 Jan 2018 16:06:52 GMT

I think you have answered yourself. Then it is needed to choose TRIGSEL=0b11 in particular SDADC configuration register and that's it.

Re: Using eMIOS as a hardware trigger for SDADC

erickarr — Thu, 25 Jan 2018 16:28:01 GMT

Hi David,

Thank you for your response.

I have that configuration in place on the SDADC as well, but I am unaware how an eMIOS input is used as an input into the SIUL2.

In the top right corner of the block diagram, you see the mapping of the eMIOS into the SIUL2 as a start trigger and mux advance.

If I have configured the SDADC for a trigger input of type MSCR, and if I have configured the appropriate SIUL2 MSCR register, how do I configure the eMIOS pin as my hardware trigger input?

Thanks,

Eric

Re: Using eMIOS as a hardware trigger for SDADC

davidtosenovjan — Mon, 29 Jan 2018 14:06:41 GMT

You don't need to setup Scythian else. Mentioned MSCR register connects eMIOS internal channel to SDADC trigger.

If you want to use emios external pad, configure also following MSCR registers (considering PJ7 pad as an example):