TCP Urget Flag Support

Do any WIZnet chips support sending a TCP packet with the URG (Urgent) flag set? I see that the W6100 can set the PSH (Push) flag, but that is all.

I of course could implement/use a software TCP/IP stack in conjunction with MACRAW mode, but that seems to only be available on one socket, and going that route looses most if not all of the advantages of going with a WIZnet device.

Then you generally lose the value of the hardware networking stack acceleration.

Why do you need URG flag? What are the possible scenarios?

I was looking at implementing a TELNET system on a microcontroller and to be fully compliant I need to be able to send TCP packets with the URG flag in order to implement the Synch system.

Annoyingly, there doesn’t seem to be any alternative to the URG flag despite modern standards suggesting it no longer be used.

Ok, I see. Afraid there’s no such functionality within the chip. The workaround could be withholding putting further data into the TX buffer (its size is relatively small - by default 2kB) and inject telnet control code in between current and further data.