Lost on LAN line

[cncmachineguy]

Ok, let me give this another go. In the beginning there was the ISA bus. It was quite simple to make a card to plug into it and have I/O using an 8255 or simular. Then that was replaced with the PCI bus. Not near as useful from a homebrew interface card. But we still had the parallel port. If used in EPP mode, quite high speed could be had using a pretty simple homebrew card. I have a card now that gives me 64 I/O lines, all through the pport. This is all needed for my current CNC control.

But the parallel port is going away also, so we are left with few choices if we want to use our computers for anything other then surfing the net or playing games. we have:

USB - Great interface but not realtime. Service could be as long as 10mSec delay. No good for machine control
FireWire - Don't know much about it, may be great but not widely available
PATA - I am looking into this as it is based on ISA bus. But not too motivated as that seems to be vanishing also.
FDD - same as PATA
SATA - may be viable, but most likely too much trouble.

Brings us to the NIC. It has been used for what I want to do, including available drivers for the PC side of things. (The link I posted in the first post shows a finished product of that which I desire). So for me, that is the hard side and its done already. I just need to come up with a suitable way to have a PIC talk to a NIC. In a fashion much faster then 115K. Now the ethernet capable PIC sounds VERY intresting. I will surf that a bit. Keep in mind I have NO idea what it takes to talk to a NIC. In my mind I think it must be pretty hard as I have read things like TCP/IP stack and UDP protocal. Lots more stuff I don't even want to think about.