Enabling Pmod wifi with FPGA board

[hola]

Please note that I do not have enough knowledge in this field, so kind explanation would be appreciated.

 

Hi, I am currently planning on enabling wireless communication with FPGA board (I am considering VC707 for the board). 

Since the required datarate is about 30Mbps, I selected your product Pmod Wifi for the wireless module which can support up to 54Mbps datarate.

In the process of enabling wireless communication, many questions came up to me, and I am writing to request if you guys can answer my questions.

 

To learn how to use Pmod wifi, I watched the youtube video explaining how to use it with digilent FPGA board.

My first question at this point is that can I just follow the steps explained in the youtube video even with VC707 board which is not your product. 

Microblaze seems to be used in the process. Just to check, Microblaze is also supported with all the Xilinx FPGA board including VC707?

 

My second question is that could I communication data through FPGA board and Pmod wifi by using SPI communication?

If possible, could you please provide information about the process such as Pmod wifi module protocal.

For example, which data to be transmitted to Pmod wifi from FPGA board to send 1011001 (example data) through wireless communication?

 

Since I am very new to this field, it is hard to come up with proper vocabulary...

I hope you could understand my words and appreciate your help in advance!

[JColvin]

Hi @hola,

I'd like to offer some words of caution regarding your goal of transmitting wireless data with the Pmod WiFi. I will start by saying that yes it is technically possible to do what you want, but there are a few things to consider.

- The 54 Mbps listed on the Pmod WiFi is the theoretical maximum rate available through WiFi 2 networks (previously known as 802.11g). These rates, quoted from Microchip's datasheet, are really only obtainable in specialized lab setups. The speed you will get will be much lower than that due to latency, overhead associated with the software stacks, and general quality and traffic on the actual WiFi network you will connect to. Because of this, I don't have a real-world transfer rate to quote for you, but I would also not be putting all of my expectations that the 30 Mbps will for sure be achieved.
- "My first question at this point is that can I just follow the steps explained in the youtube video even with VC707 board which is not your product." You would not be able to use these steps directly, no. A number of the steps used various board file materials from Digilent to help enable the connections. You might be able to download Digilent's vivado-library, https://github.com/Digilent/vivado-library, and just add the Pmod WiFi IP to your block design and get the appropriate AXI and MicroBlaze connections made, but I don't know what other nuances might be associated with that.
- "My second question is that could I communication data through FPGA board and Pmod wifi by using SPI communication?" All protocol and associated WiFi stack materials are available in the documentation and driver/src materials for the Pmod WiFi: https://github.com/Digilent/vivado-library/tree/master/ip/Pmods/PmodWIFI_v1_0. The demo that is closest to what you are describing would be the HTTPServer demo where you are able to set and view the status of different IOs on the FPGA through a locally hosted .html page. It does not offer streaming of data so to speak, though the echo server/client demos could probably be adjusted on both the board and host computer application side to change this behavior.
- Since you are new to this field and will probably want to be doing a lot of proof of concept and other development work (though I don't know your system constraints or budget) I would probably recommend getting a lower cost board than the VC707 to get some development testing done. You can also do a lot of development work in Vivado and SDK/Vitis directly without any hardware to make sure all of the board designs and applications are able to build correctly if you wish.

Thanks,
JColvin

[hola]

Thank you for your kind answer!

 

As you suggested, I bought Arty S7 board and Pmod Wifi to try testing the wireless communication.

Now, I am referring the example "HTTPServer" project in the Github.

It seems that the code is requiring external SDCard to store and send data to clinet.

By the way, I would like to use internal memory instead of SDCard, and wonder if there are any example codes using internal memory I could refer to.

If not, your advice on this would also be very welcome.

 

I truly appreciate for your help!

 

Thanks,

Hola

 

On 10/29/2021 at 4:37 AM, JColvin said:

Hi @hola,

I'd like to offer some words of caution regarding your goal of transmitting wireless data with the Pmod WiFi. I will start by saying that yes it is technically possible to do what you want, but there are a few things to consider.

- The 54 Mbps listed on the Pmod WiFi is the theoretical maximum rate available through WiFi 2 networks (previously known as 802.11g). These rates, quoted from Microchip's datasheet, are really only obtainable in specialized lab setups. The speed you will get will be much lower than that due to latency, overhead associated with the software stacks, and general quality and traffic on the actual WiFi network you will connect to. Because of this, I don't have a real-world transfer rate to quote for you, but I would also not be putting all of my expectations that the 30 Mbps will for sure be achieved.
- "My first question at this point is that can I just follow the steps explained in the youtube video even with VC707 board which is not your product." You would not be able to use these steps directly, no. A number of the steps used various board file materials from Digilent to help enable the connections. You might be able to download Digilent's vivado-library, https://github.com/Digilent/vivado-library, and just add the Pmod WiFi IP to your block design and get the appropriate AXI and MicroBlaze connections made, but I don't know what other nuances might be associated with that.
- "My second question is that could I communication data through FPGA board and Pmod wifi by using SPI communication?" All protocol and associated WiFi stack materials are available in the documentation and driver/src materials for the Pmod WiFi: https://github.com/Digilent/vivado-library/tree/master/ip/Pmods/PmodWIFI_v1_0. The demo that is closest to what you are describing would be the HTTPServer demo where you are able to set and view the status of different IOs on the FPGA through a locally hosted .html page. It does not offer streaming of data so to speak, though the echo server/client demos could probably be adjusted on both the board and host computer application side to change this behavior.
- Since you are new to this field and will probably want to be doing a lot of proof of concept and other development work (though I don't know your system constraints or budget) I would probably recommend getting a lower cost board than the VC707 to get some development testing done. You can also do a lot of development work in Vivado and SDK/Vitis directly without any hardware to make sure all of the board designs and applications are able to build correctly if you wish.

Thanks,
JColvin