Programming the AM1808 PRU as an SPI port

Mellissa Dalby

Intellectual 295 points

Has any one ever programmed one of the PRU's to perform as an SPI port?

I would like to get a clue has to how that could be done.

Also, can the PRU read the RTC in the main processor?

over 14 years ago

0 melissaw over 14 years ago

TI__Genius 15910 points

Hi Mellissa,

We are assessing the possibility of emulating SPI using the PRU and will get back with you. What are your requirements for the SPI port, including speed?

Regards,

Melissa

0 dabuan over 14 years ago

TI__Genius 14545 points

Mellissa Dalby said:
Also, can the PRU read the RTC in the main processor?

The peripherals that the PRU can access are specified in the Memory Map Summary of the AM1808 Datasheet.

0 Mellissa Dalby over 14 years ago in reply to dabuan

Intellectual 295 points

Drew Abuan said:

Also, can the PRU read the RTC in the main processor?

The peripherals that the PRU can access are specified in the Memory Map Summary of the AM1808 Datasheet.

[/quote]

Ahh, it looks like the RTC IS in the PRU SubSystem memory map, so I'm thinking that should work.

Thanks

0 Mellissa Dalby over 14 years ago in reply to melissaw

Intellectual 295 points

mwatkins said:

Hi Mellissa,

We are assessing the possibility of emulating SPI using the PRU and will get back with you. What are your requirements for the SPI port, including speed?

Regards,

Melissa

I the SPI device in mind is byte access and a minimum speed of 1 MHz would likely do the job.

I bet bit-banging in the PRU would probably work, but we'll see...

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Programming the AM1808 PRU as an SPI port