WIZnet Developer Forum

Wiz750SR with TCP_NODELAY

with Wiz750SR module there is the possibility to have socket open with TCP_NODELAY set? i’m using it in a application where the comunication is done with small packet frequent and in near real time, bidirectional, with the high speed working i will see some delay on the packet reception, but mainly is not stable like it depends from other packets… on the network there is only one Wiz750SR and a Gigabit Ethernet adpater of the PC. (maybee in future can be also a raspberry or two on the same network, but not connected to internet or other device…) i can disable on the PC software the TCP_NODELAY, but if there is on the Wiznet module i solve only a partial of the problem, not the complete…

Best Regards…
Davide Valdinoci

WIZ750SR has TCP_NODELAYACK set.
If you want to disable it, you can modify the code to use it.
Please Tell me more about your problem.

the size parameter in the data packing section, can be used to send immediately the tcp message, when received the number of chars indicated? and in case can be combined with the Time (in ms) to ship immediately when the timeout between char expiry?
i have see in the debug message in my application that sometimes the message whas grouped… i have a very high number of message from the 750sr module to PC with message composed of 6/8 bytes message… trasmitting at 38400baud at a maximum speed rate of 330 at seconds… then connection is with 100mb ethernet adapter… apparently the problem seem to appear on laptop of last generation with gigabit ethernet, processor of AMD a6 or intel i3, not with Intel I5 (i have check with a same operating system). or Fixed PC with 4 core intel processor… and windows XP/Win7 notebook with DualCore processor… i have set in the PC program the TCP_NODELAY…

Sorry, i don’t understand your problem.

Is this your problem? Please tell me the specific symptoms.

Do you want to add delay? It is possible by modifying code. please tell me more about “the timeout between char expiry?” Even if the response packet is not sent immediately, the ACK is sent automatically, so Timeout doesn’t occurred for the TCP connection. It may be different if you are saying a different timeout.

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