• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 97 subscribers
  • Views 659 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

RTOS/TMS320C6654: SPI Chip Select, Manual Control

LazyHD
Expert 1060 points

Part Number: TMS320C6654

Tool/software: TI-RTOS

I have a simple question but I can't seem to find the answer in the documentation.

In SPI_v0_HWAttrs, what is the csNum variable exactly ? Is it 0 or 1 corresponding to SPISCS0 and SPISCS1 respectively ?

What if I want to control the chip select by software without the driver being involved ? I have more than 2 slaves on the bus and I connected them to other GPIO pins on the DSP.

If this information is shown in any of the documentation, can you point me to it ? I can't seem to find it.

Environment:
CCS9
Processor RTOS SDK: 5_02_00_10

  • 0
    TI__Guru**** 161600 points

    Hi,

    In SPI_v0_HWAttrs, what is the csNum variable exactly ? Is it 0 or 1 corresponding to SPISCS0 and SPISCS1 respectively ?

    Yes, csNum corresponds to SPISCS0 and SPISCS1.

    As for using GPIOs for additional chip selects. Yes, this is possible, but there is no reference driver for this. You should write the software yourself. Also in this case I think it will be easier to use the SPI in 3pin mode (see section 2.6 SPI Operation: 3-Pin Mode in SPI user Guide: )  and use only GPIOs as CS signals.

    Best Regards,
    Yordan

  • 0 in reply to Yordan Kovachev
    Expert 1060 points

    Thank you, I thought 3 pin mode means combining the MOSI and MISO pins. It is clear now, thanks again.