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EB023 ethernet board can't send data at high frequency
Posted: Tue Dec 07, 2010 7:18 pm
by benp
It is not possible to send data at a high rate with the ethernet board.
Example:
CASE 1:
- Send 3 bytes (Tx start/Sendbyte/Sendbyte/Sendbyte/Tx end)
Wait 500 ms
Repeat forever
All datas are received
CASE 2:
- Send 3 bytes
Wait 100 ms
Repeat forever
Some send packets are missing on the computer.
I use TCP mode. EB023 is server, computer is client.
Can you explain this?
I can send you an example program which show the problem.
I use the following config:
EB006+18F4520 (same with 18f2680 or 16f887)
EB023
Direct connection to a computer with RJ45 CAT 5 cross-over cable (tested with the local network to)
Netstuff program as client (java program tested too)
wireshark for sniffing
Re: EB023 ethernet board can't send data at high frequency
Posted: Thu Jan 06, 2011 10:07 pm
by benp
If this can help because I still have no answer.
I performed more test with the following flowcode program:
I use netstuff to connect the computer to the EB023 Eblock.
It can be downloaded here for example:
http://jacquelin.potier.free.fr/networkstuff/
With this program
If the delay between 2 sending is 0.2s, all datas are received
If the delay between 2 sending is 0.1s, approximatively half packets are missing
The half packets are missing from the beginning (It should be a data overflow)
Under 0.1s, more data are missing.
If I use twice data with a 0.2s period, all datas are still received.
It could a flowcode or a wiznet bug but maybe I am wrong.
I had a quick look at the flowcode macro. The macro seem wait for the end of the last I2C sending for a new sending.
There are some bug on the wiznet W3100A module but I don't know if mine is some of them.
Link for W3100A possible bugs:
http://www.wiznet.co.kr/Sub_Modules/en/ ... F_KeyWord=
http://www.wiznet.co.kr/Sub_Modules/en/ ... _NUM=23049
Re: EB023 ethernet board can't send data at high frequency
Posted: Fri Jan 07, 2011 11:40 am
by Benj
Hello,
Thats seems strange. Maybe as you say its a bug with the Wiznet or something along the lines that the Wiznet needs time to send out data packets before the next packet can be put together.
Can you simply use the 0.2 second timing but cram as much data into each packet so that you can acheive the throughput you require.
I have some experience working with the module but only doing fairly basic tasks and not handling large amounts of high speed streaming data.
Re: EB023 ethernet board can't send data at high frequency
Posted: Wed Jan 12, 2011 8:47 pm
by benp
Is there a way to know if the problem come from the wiznet, I2C or flowcode.
I would like to reach a 150 Hz sending frequency. That's under the theorical Wiznet capabilitie but it is praticaly impossible reach.
Re: EB023 ethernet board can't send data at high frequency
Posted: Thu Jan 27, 2011 6:49 pm
by benp
I will try to have a look at the I2C line to see what's going on.
Is ICD scope only working with flowkit as explained here:
http://www.matrixmultimedia.com/mmforum ... =26&t=7376
Or is it possible to use it with EB006-00-07 now?