SK-AM64: General questions to clarify if the board answers our needs

Jameel Magzal

Prodigy 70 points

Part Number: SK-AM64

We want to use the following EVM;

https://www.ti.com/tool/SK-AM64#included

to evaluate the following application:

To simultaneously acquire data from two SPI ports; a transaction each 0.2msec, 150 bytes each transaction from each port, clock speed of 8Mbits/sec
This data is gathered in the Linux core and continuously sent in larger packets through wi-fi to a smart phone. Expecting a transfer rate of ~1.5Mbytes/sec.

Questions:

Is the SK-AM64 good for this?
Is the out of the box Wi-Fi board option is our starting point? Do you have libraries for WIFI on this SK-AM64?, Do we only need to do is program the SPI transactions and create the Wi-Fi blocks, and send through the wi-fi libraries of the SK-AM64?
planning future to use the onboard USB to connect to host and stream the data, is that possible? and how complicated should we expect it to be to get it working ?

Best Regards,

Jameel

over 1 year ago

0 Pekka Varis over 1 year ago

TI__Mastermind 27050 points

In theory yes, the bandwidth you are targeting is possible. 0.2millisecond, 200microsecond, transaction interval sounds like you are targeting not just bandwidth but some sort of real-time performance as well, which would mean you should use PREEMPT_RT (RT-Linux).

As for the interfaces (SPI, Wi-Fi (just an Ethernet device), USB), they are all standard Linux interfaces, so writing a gateway/bridge application to take data from one and send it over another is possible. Wi-Fi is just and Ethernet device so interface is just like any Ethernet (sockets). SPI has an example https://software-dl.ti.com/processor-sdk-linux/esd/AM64X/latest/exports/docs/linux/Foundational_Components/Kernel/Kernel_Drivers/SPI.html at the bottom https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/spi/spidev_test.c . USB is a standard USB interface use it as with any Linux based SoC.

Also please note the board https://www.ti.com/tool/SK-AM64B has the newer silicon revision, which is the default silicon the SDK uses. I would not recommend to use the older revision https://www.ti.com/tool/SK-AM64 for anything.

Pekka

0 Jameel Magzal over 1 year ago in reply to Pekka Varis

Prodigy 70 points

Hi Pekka,

thank you for the fast reply, much appreciated

Regarding the WIFI/USB, when you say standard Linux interfaces (I am not fully familiar with Linux and will probably need to outsource any work done here), does it mean there are examples on how to do this? if we for example wanted to connect to the device using a smartphone and receive the data, does it require special implementation on the firmware side? what about the host application side?, and what if we used windows laptop, do things change or is it same implementation? are there any examples that we can look at?

Jameel

0 Pekka Varis over 1 year ago in reply to Jameel Magzal

TI__Mastermind 27050 points

Yes. User space application using networking (Wi-Fi), USB, or SPI based on standard Linux interfaces should be fairly basic for a software engineer.

Wi-Fi is just an ethernet device, so SW interface is the same as with wired Ethernet, open a socket and just write and read from it, driver below this comes from the Wi-Fi chipset vendor and in most cases should be upstreamed to already be part of the kernel. USB interface is at https://www.kernel.org/doc/html/v6.1/driver-api/usb/index.html .

You can look at any Linux USB or networking example, this is not TI specific.

0 Jameel Magzal over 1 year ago in reply to Pekka Varis

Prodigy 70 points

So there shouldn't be any major issues using RT-Linux, the SPI example you provided and add networking and still be able to acquire the data in 200us SPI transactions, accumulate and then send using Wi-Fi or USB

0 Jameel Magzal over 1 year ago in reply to Jameel Magzal

Prodigy 70 points

I went through some of the support material, i see there is this

https://software-dl.ti.com/processor-sdk-linux/esd/AM64X/08_02_00_23/exports/docs/system/Demo_User_Guides/WiFi_OOB_Demo_User_Guide.html

can you confirm this demo works on the new revision ?

0 Pekka Varis over 1 year ago in reply to Jameel Magzal

TI__Mastermind 27050 points

8.2 SDK is quite old (May 2022), back then the default was the old SK-AM64 (SR1.0). https://software-dl.ti.com/processor-sdk-linux/esd/AM64X/latest/exports/docs/system/Demo_User_Guides/WiFi_OOB_Demo_User_Guide.html same link but "latest" instead of a specific version For any product development please use SK-AM64B (SR2.0). Currently this is 9.0 from July 2023. We swithced to default to SR2.0 silicon a few releases ago.

Regardless Wi-Fi demo has been there for several releases, current 9.0 assumes SK-AM64B (SR2.0). Also any product should use SR2.0. You will need to do one file rename modification to run on SR1.0, but use SR2.0 SK-AM64B for any development.

Pekka

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SK-AM64: General questions to clarify if the board answers our needs