Enabling Raw Frame Support and Promiscuous

[owaits]

It took me a while to work out how you enable both raw frame support and promiscuous together as the readme only gives an example for enabling one macro. Can I suggest updating the example to include enabling two macros as bellow.

compiler.cpp.extra_flags=-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT -DQNETHERNET_ENABLE_PROMISCUOUS_MODE
compiler.c.extra_flags=-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT -DQNETHERNET_ENABLE_PROMISCUOUS_MODE

It all seems obvious now but many of the forum posts I read suggested quotes which lead me down the garden path. In the end I had omitted the -D from QNETHERNET_ENABLE_PROMISCUOUS_MODE as I had not spotted in the readme that this had been appended to QNETHERNET_ENABLE_RAW_FRAME_SUPPORT.

Amazing library though, thank you so much for your work on this.

[ssilverman]

Thanks for using QNEthernet and for the suggestion.

I'm curious, can you point me to where you read about using quotes?

[ssilverman]

Also, I'm curious: what did your non-working attempts look like? Would you mind listing them? I find it's sometimes good to put "what not to do" in addition "what to do". It appears this might be helpful here.

[owaits]

The forum article that suggested quotes was this https://forum.arduino.cc/t/how-to-specify-multiple-extra-compiler-flags/994083

Here are some of the variants I tried:

compiler.cpp.extra_flags=-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT, QNETHERNET_ENABLE_PROMISCUOUS_MODE

compiler.cpp.extra_flags=-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT -QNETHERNET_ENABLE_PROMISCUOUS_MODE

compiler.cpp.extra_flags="-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT -QNETHERNET_ENABLE_PROMISCUOUS_MODE"

compiler.cpp.extra_flags='-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT -QNETHERNET_ENABLE_PROMISCUOUS_MODE'

compiler.cpp.extra_flags=-QNETHERNET_ENABLE_PROMISCUOUS_MODE -DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT  //Resulted in compile error

I have been trying to receive LLDP packets, in the end I did not need to enable it as the reason it was not working was because of the line

if (size < EthernetFrame.minFrameLen() - 4)

in the RawFrameMonitor example. This ignores any raw packets over about 41 bytes and the LLDP packets where 491 bytes.

[ssilverman]

[The reply appears to be missing the forum link.]

Thank you for those incorrect attempts. I'm going to think about how I'd like to improve the documentation.

That code in RawFrameMonitor checks for less than 60 bytes (64 - 4) and prints "SHORT Frame"; it prints the whole frame if >= 60 bytes. I don't think it ignores 491-byte frames?

[owaits]

I have updated my comment to include the forum link. I had over simplified the RawFrameMonitor example as I just wanted to see the raw data printed to serial. The example code as written is fine.

[ssilverman]

What do you think of these modifications to the README:

Next, create a platform.local.txt file in the same directory as the
platform.txt file and add the options you need. The contents of the properties
are exactly the same as if adding them to the command line. For example, to
enable raw frame support and disable DNS:

compiler.cpp.extra_flags=-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT -DLWIP_DNS=0
compiler.c.extra_flags=-DQNETHERNET_ENABLE_RAW_FRAME_SUPPORT -DLWIP_DNS=0

Each additional option is simply appended. No commas or quotes are required
unless they would be used for those same options on the command line.
See https://github.com/ssilverman/QNEthernet/issues/54#issuecomment-1788100978
for some incorrect variants.

[ssilverman]

See commit 5484704.