7i96 Ethernet Connection

Can the 7i96 be connected to a router port or does it have to be directly to the PC?

it _can_ be connected through a switch (not a router) though this will
increase latency because switches are normally store+forward devices that
wait till the end of a packet before sending it to the downstream port..

I would not suggest this in general, because you want the host Ethernet
MAC dedicated to real time so normal network traffic does not interfere with
real time traffic timing. The only case where a switch makes sense is if you
have multiple real time Ethernet cards on one host port..

OK thanks. I was thinking I could just connect it to a WAP temporarily so I could have network access while configuring the 7i96 and then connect it properly for real time use. It should be easy enough to try once I get the card. I'm also looking forward to being able to use 4x microstepping.

I am having a problem with the network interfaces. One is an ethernet NIC, the other is a USB Wifi dongle. They both work, but only one at a time. In order to communicate with the 7i96, I have to unplug the wifi module. In order to get internet, I have to install the wifi module but then the ethernet doesn't work. Is there a way to work with both at the same time? With wifi enabled, doing a ping 10.10.10.10 shows no route to host because it is trying to ping over wifi and not the ethernet card. Thanks.

Yes, you need to configure the interfaces separately

Typically, using the GUI, the USB--Ethernet dongle needs be configured for
"auto" or "Automatic -DHCP" for you local internet access and the local real time
connection to the 7I96 needs to be setup for "manual" in the IPV4 tab

That's exactly how I had it. The problem was actually with the fact that ifconfig is basically deprecated in Debian 9. After configuring the ethernet interface with NetworkManager, it all started working. I have both the PC and 7i96 connected to a router in WAP mode so it won't work with an IP of 10.10.10.10. However, that's not a problem since when linuxcnc is running, the PC can no longer see the network.

BTW, I like my 7i96 board. The motors run smoother at 4x microstepping and no more latency excursions.

Have you considered adding a USB-->WIFI or USB-->Ethernet dongle for normal internet access? ( unless blocking internet/localnet access when machining is a deliberate choice )