topic FRDM-K64F lwip tcp echo in Kinetis Software Development Kit

FRDM-K64F lwip tcp echo

roymessinger — Fri, 21 Apr 2017 21:59:55 GMT

Doing my first steps with the lwip source code, I've tried running the bm source demo of the tcp echo from the ksdk. What I don't understand is that in the overview it is written:

"...The application sends back the received TCP packets from the PC, which can be used to test whether a TCP connection is available."

But at the end, when running the demo I'm receiving just this:

Reply from 192.168.0.102:7, time 0 ms OK
Reply from 192.168.0.102:7, time 0 ms OK
Reply from 192.168.0.102:7, time 0 ms OK
Reply from 192.168.0.102:7, time 0 ms OK
Reply from 192.168.0.102:7, time 0 ms OK

But in the demo I'm sending:

echotool 192.168.0.102 /p tcp /r 7 /d hello

So, how come I'm not receiving the hello word? No matter what I'm writing to the echo tool, I'm always receiving the same 5 lines. I thought I should receive the hello, or any other word I'm sending (isn't this what echo server mean?).

What am I missing here?

Re: FRDM-K64F lwip tcp echo

danielchen — Mon, 15 May 2017 07:02:18 GMT

Hi roymessinger

You get 5 lines because this tool tried to send "hello" 5 times. 5 is not the length of "hello", it is the default value

You can change the tried time by /n

Have a great day,
Daniel

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Re: FRDM-K64F lwip tcp echo

roymessinger — Sat, 10 Jun 2017 20:44:43 GMT

Hi danielchen@fsl ,

Thanks for your help.

Still, the main idea of echo server is that it sends back the text it received. Isn't it?

I did not get anything here...

Roy