Got linuxcnc running with latest rtai on 2.6.38.8

I finally got linuxcnc up and running on my SandyBridge CPU. Some key points were:

you have to configure linuxcnc with the correct paths- mine is:
./configure --prefix=/usr --with-realtime=/usr/realtime --with-kernel-headers=/u
sr/src/linux-headers-2.6.38.8-rtai --with-module-dir=/lib/modules/2.6.38.8-rtai

Another tricky part is that I need to load the rtai kernel modules separately before running linuxcnc or else i get errors with rtapi. I made a small script called "load_rt" which I run before running linuxcnc for the first time
#/bin/sh
insmod rtai_hal.ko
insmod rtai_sched.ko
insmod rtai_fifos.ko
insmod rtai_math.ko
insmod rtai_wd.ko
insmod rtai_sem.ko
insmod rtai_shm.ko
insmod rtai_mq.ko
insmod rtai_tbx.ko
insmod rtai_mbx.ko
insmod rtai_serial.ko

Another tricky aspect was my pcie parallel port card needs to use the port 0xe010 (not 0x378). I have a CNC 3040 which are probably pretty common judging from all the youtube videos about them, and by their low cost and high quality (compared to a home-built or plastic built one at least), and I had to make a custom configuration but that wasn't too tough.

One problem that remains is that I can't use the intel video card driver - it's using the VESA driver. I think this is because the intel driver requires acpi and I removed that for rtai. So my highest monitor resolution is 1024x768. And this probably means that opengl is not using the hardware acceleration and doing software render only.

But I have to feel good that I can use my most recent PC to use my CNC machine.

Adding that I got linuxcnc running with the intel graphics driver in a higher resolution mode. It took a few changes:

-I had to rebuild rtai with acpi (the intel driver apparently requires acpi)
-I had to remove AppArmor otherwise it would not open the display- but this could have been related to:
-I had to remove and reinstall my xserver-xorg-video-intel (before this loading the rtai latency module would cause a crash)

So yes it feels good to get it working in high resolution. I hope this might help others including myself if ever I need to rebuild it again.