[CYW43907] Transmitting and receiving raw 802.11 frames

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DaRa_4398441
Level 1
Level 1

I'm using a CYW943907AEVAL1F board to evaluate using CYW43907 in an upcoming board design.  I'm using the latest release of WICED Studio.

My application needs to transmit and receive raw 802.11 frames including the layer 2 (MAC) header.  I have a working example of receiving frames in monitor mode using wwd_wifi_set_raw_packet_processor() and wwd_wifi_enable_monitor_mode(). This is based on the snip.packet_filter example code.  Unfortunately, I need a few hooks that I can't find digging through the SDK which may make this part not feasible for this project.

  1. If I call wwd_wifi_set_channel() before entering monitor mode, will the transceiver stay tuned to the requested channel while monitor mode is active?  If so, can I later call wwd_wifi_set_channel() again without exiting monitor mode, so I can capture packets for fixed time intervals on different channels?
  2. When I'm receiving raw frames in monitor mode, how can I query RSSI for each received frame, or in some way differentiate the receive power of incoming frames?
  3. This question is not related to monitor mode - it is about raw frame transmission.  How can I transmit a raw 802.11 frame that is not data.  My application will create a custom 802.11 management frame (providing its own complete and valid 802.11 MAC header) that I need to transmit on a specified channel.  This is not a data frame and does not have an Ethernet header, so the wwd_network_send_ethernet_data() function does not seem appropriate.

For what it's worth, I also sent these questions in a direct technical support case and received a terse and discouraging response, "We do not recommend using Monitor mode in CYW43907 as it is not tested."  I'm not exactly sure what to make of that.

Finally, if the CYW43907 cannot do what I need, are there any other Wireless MCU parts that you'd recommend for this use case?  The application will be RTOS-based or bare-metal.  The CYW43907 is a very enticing solution with its Cortex-R application core, plentiful on-chip SRAM, and rich set of I/O peripheral support.  Other Wireless MCUs on the market are much less performant.

Thank you,

David

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1 Solution
KotnaniK_71
Employee
Employee
50 likes received 25 likes received 10 likes received

Hi David,

I regret to inform you that we haven't tested the monitor mode of CYW43907 and we won't recommend using monitor mode. Also, if there is any problem arises while using the monitor mode, it would be very difficult for us to help you in future.

We recommend 43455 Wifi radio module which has 800KB SRAM. Kindly refer below document to know more about 43455 and let us know if 43455 chip is feasible for your project.

https://www.cypress.com/file/358916/download

Apologies for the inconvenience caused.

Regards,

Pavan.

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3 Replies
KotnaniK_71
Employee
Employee
50 likes received 25 likes received 10 likes received

Hi David,

I regret to inform you that we haven't tested the monitor mode of CYW43907 and we won't recommend using monitor mode. Also, if there is any problem arises while using the monitor mode, it would be very difficult for us to help you in future.

We recommend 43455 Wifi radio module which has 800KB SRAM. Kindly refer below document to know more about 43455 and let us know if 43455 chip is feasible for your project.

https://www.cypress.com/file/358916/download

Apologies for the inconvenience caused.

Regards,

Pavan.

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Thank you for the response.  It looks like 43445 is a standalone WiFi link controller that does not have a core dedicated to hosting a separate application.  Is that correct?  What drew me to the 43907 is the embedded application processor.

If this is correct, can you suggest a Cortex-M or Cortex-R based application processor that has an SDK with existing driver support for 43455 part you recommend?

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Hi David,

You're right. 43455 is a standalone radio WiFi module that does not have a dedicated core to host an application.

We have checked internally and unfortunately there is no existing driver support with SDK for 43455 that matches your requirement.

Sorry for the inconvenience.

Thanks.

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