• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 82 subscribers
  • Views 294 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.

TMS320F28375D: C2000™ microcontrollers forum

Joakim
Intellectual 1810 points
Part Number: TMS320F28375D

We are now developing a new board with DSP TMS320F28375D and we would like to interface it using the external memory interface with a synchronous Ram and an asynchronous Ram. I found an example in documentation and I have a look at your evaluation kit documentation.

My question is about the address pin connect to GPIO generic (please refer to the attached picture (EMIF GPIO pin and FLASH A[13:18] pin

•             Is it still possible to read and write memory with the same performance of connecting all the address pin to the dedicated GPIO?

•             Is it still possible using DMA transfer?

•             How we can configure generic pin to be used like EMI address pin?

TMS320F28375D question.docx

  • 0
    TI__Guru** 115271 points

    Hi Kenka,

          Is it still possible to read and write memory with the same performance of connecting all the address pin to the dedicated GPIO?

    The figure attached is only using MSB address lines incase the target memory is large. Are you asking you want to use all the address lines in GPIO mode ? I am not sure why would someone do that. On performance, no it'll not be same because you have to emulate the address on GPIO via SW which will take few CPU mips.

    •             Is it still possible using DMA transfer?

    CPU has to drive the address pins. DMA can not emulate it. If you are connecting only few MSB address bit via GPIO then yes DMA can be used for memory range which does not need GPIO pin toggle. So every time address need to be incremented via GPIO pin, CPU need to do that and then trigger DMA transfer.

    [quote] •             How we can configure generic pin to be used like EMI address pin? [/quote[

    I did not get this question? Do you mean how to configure generic pin as EMIF pin? If yes, then you can refer the EMIF example for the same. It's GPIO mux setting which need to be changed to select EMIF function on a pin.

    Regards,

    Vivek Singh

  • 0 in reply to Vivek Singh
    TI__Intellectual 1810 points

    Thanks for the answers,

    I would need some further support, please comment 

    1. Can I use the chip select 2, 3, 4 of EMIF1 interface for Synchronous chips RAM connected to the same bus?
    2. Please confirm if we can use DMA transfer on synchronous RAM connected to EMIF1?

  • 0 in reply to Joakim
    TI__Guru** 115271 points

    Hi,

    Can I use the chip select 2, 3, 4 of EMIF1 interface for Synchronous chips RAM connected to the same bus?

    I think you mean ASYNC RAMs. Please confirm.

    Please confirm if we can use DMA transfer on synchronous RAM connected to EMIF1?

    Yes, DMA can be used to transfer data via EMIF1.

    Regards,

    Vivek Singh

  • 0 in reply to Vivek Singh
    Prodigy 150 points

    The RAM I mean I s a synchronous RAM, the datascheet is attached.           

    We would like to use this RAM because it is cheaper than the asynchronous types.

    So I’d like to know if it is possible to use EM1CS[4:2] even for synchronous ram, I have some doubts because I see in this table in “TMS320F2837xD Dual-Core Microcontrollers Technical Reference Manual” that explain that this pins are “Specific to Asynchronous Memory”. If is true we can have only one synchronous chip on EMIF 1 interface ( using chip select 0).

    Even the second question is referred to synchronous ram chip, It is possible to use DMA transfer?

    sdram_K4S643232E.pdf

  • 0 in reply to ELISA SACCHI
    TI__Guru** 115271 points

    Hi,

    Only CS0 can be used for SDRAM interface. Other chip select only supports ASYNC RAM.  So you can only use one SDRAM device with EMIF1.

    DMA transfer is supported for SDRAM as well as ASYNC RAMs.

    Regards,

    Vivek Singh