where is RTSI trigger lines in 6711 card

Hi there,

  I have a PCI-6711 card. The manual said it supports the RTSI trigger line to connect the external clock as the timing source. I try to find the pin associate with the RTSI in the layout for PCI 6711 but I didn't see any. I only see PFI8/GPCTR0_SOURCE. Is it the same thing? I am pretty confusing how to use external clock to replace the internal software-based clock. Thanks.