BCM43340: is there an API to debug the internal state machine

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Anonymous
Not applicable

i am seeing an issue with this chipset where it seems like data i send to it over SDIO is not being sent out over the air. this is what i am trying to do

1. associate with an open AP

2. perform a socket connect() - this is supposed to connect to a server which is also associated with the same AP.

My system is using LWIP for the network stack. I can trace down the connect() call all the way to the point where my wifi driver sends the connect data to the chip over the sdio interface. i am running Wireshark on a separate machine which is in 'monitor mode'. So in theory I should be able to see the connection request that is sent out by the broadcom chip. But I don't see this data in Wireshark. My theory is that the chip is not sending out data it receives over SDIO.

Is there any reason why this would happen? Can we use any APIs to debug what the chip is doing?

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JoYi_1844281
Level 6
Level 6
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Do you device get IP address from your DHCP server ?

Could you ping your server if device's IP got ?

Could you saw the TCP 3 way handshake between your device and server via wireshark capture ?

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Anonymous
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Yes. The device gets the IP from the access point when it associates with the AP. so when i perform the connect() it already has an IP.

Do you mean ping my device from the machine that is hosting the server? I haven't tried that.

No. So this is what is going wrong. I never see the 3-way handshake on wireshark even after doing an lwip_connect() from my device. I have verified that my wifi driver sends out data to the wifi chip over the SDIO interface. But the chip doesn't send out the data for some reason.

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You could ping server or Gateway from device, which you could control !

If you don't saw the TCP three way handshake , The network stack is not work or not configure well !

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Anonymous
Not applicable

i think it looks like an ARP issue. The Broadcom chip seems to be sending ARP requests, but the server machine does not respond, hence it's never able to start the TCP 3-way handshake 

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So there are only broadcast packet work now (DHCP Client)!

The ARP request send by network stack not WiFi, The WiFi CHIP only handle L2 packet and event!

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