TMS320C6746: Connecting Multiple DSPs

Michael C

Part Number: TMS320C6746
Other Parts Discussed in Thread: TMS320C6678

As shown in the attachment, I am trying to use one C6746 as the master DSP and 9 other C6746 as slaves. What will be the best option to connect them together doing data transferring? If this chip is not a good option for multi-DSP desgin, what will be the other options?

Thanks,

Michael Chen

Architecture.pdf

over 6 years ago

0 Cvetolin Shulev-XID over 6 years ago

TI__Guru 65405 points

Hi Michael,

I've forwarded this to the design experts. Their feedback should be posted here.

BR
Tsvetolin Shulev

0 Yordan Kovachev over 6 years ago

TI__Guru**** 161600 points

Hi Michael,

I would recommend using two TMS320C6678 devices connected via Hyperlink. This would give you a total of 16 DSP cores and a lot more processing power, as Hyperlink connection supports four lanes with up to 12.5 Gbaud per lane.
Consider this option, if you think that 16 cores is not an overkill for your application.

Best Regards,
Yordan

0 Michael C over 6 years ago in reply to Yordan Kovachev

Prodigy 170 points

Hi Yordan,

In this project, we need to interface with 9 different host bus protocols (each protocol will have 11 multi-drop components that sharing the host bus) and run the data process simultaneously. Can two TMS320C6678 to interface with these many components? As well, TMS320C6678 is expensive to me. Is there any other cheaper option ( one core DSP should be enough, or one DSP + one ARM core) that can provide a solution for interconnecting multiple DSPs with a moderate high speed (at least faster than I2C)? Can DSPs with RSIO or PCIe be a potential selection?

Thanks,

Michael

0 Michael C over 6 years ago in reply to Michael C

Prodigy 170 points

Another thought - Is it possible to configure GPIOs as another host bus to implement a faster data transfer? Comparing I2C to SPI on C6748, which one is faster? what is the max transfer rate that SPI could be?

0 Yordan Kovachev over 6 years ago in reply to Michael C

TI__Guru**** 161600 points

Hi,

Let me have a look at this and I will update.

Best Regards,
Yordan

0 Yordan Kovachev over 6 years ago in reply to Michael C

TI__Guru**** 161600 points

Hi Michael,

I think processors with PCIe would be a better option than I2C or SPI communication.

SPI is faster than I2C.

Best Regards,
Yordan

0 Michael C over 6 years ago in reply to Yordan Kovachev

Prodigy 170 points

Hi Yordan,

Thanks so much for all your help. Because there is no PCIe on C6746/48, I may have to use SPI for multi-drop connecting. C6746/48 has only two SPI ports but I have 9 slaves to communicate with. How can I use one SPI port to connect with 4 or 5 other C6746/48 chips - I could share the CLK, SIMO, and SOMI pins, what about the ENA pin? Can I just use GPIO to implement the function of ENA?

Best Regards,

Michael

0 Mukul Bhatnagar over 6 years ago in reply to Michael C

TI__Guru* 78385 points

Hi Michael
I have not seen anyone use GPIO for ENA functionality , can you not use SPI 4 pin mode with Chip Select.
CS can be implemented using GPIOs...
you can see some guidance on the following wiki
processors.wiki.ti.com/.../OMAP-L1x

Regards
Mukul

0 Michael C over 6 years ago in reply to Mukul Bhatnagar

Prodigy 170 points

Thanks Mukul. I will use SPI 5 pin mode with GPIOs for CS.

Regards,

Michael

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TMS320C6746: Connecting Multiple DSPs