So, the IOB in V2PRO has two tristate pins, T1 and T2. As far as I can tell, they're interchangeable in standard, i.e. non DDR, modes. In one of my designs it would help if I could get the tools to use T2 rather than the T1 it defaults too. There's slightly faster direct routing available to the T2 pin, saving 200ps from my timing budget. Sadly, the tools don't want to swap the T1 and T2 pins. Directed routing doesn't work; the route to T2 fails. I'm using ISE6.3. (waiting for SP3 before moving to ISE7.1!!) I'm not using any of the FFs in the IOB. Questions.
1) Is it true that the T1 and T2 pins are interchangeable in this mode?
2) How can I get the tools to swap the pins?
3) Is there an IOB instantiation component that includes the T2 pin? Any thoughts gratefully received. TIA, Syms.