For the spartan3 familay, A pin supports differential standards if the pin is labeled in the format “Lxxy_#”. The pin name suffix has the following
significance:
• ‘L’ indicates differential capability.
• "xx" is a two-digit integer, unique for each bank, that
identifies a differential pin-pair.
• ‘y’ is replaced by ‘P’ for the true signal or ‘N’ for the
inverted. These two pins form one differential pin-pair.
• ‘#’ is an integer, 0 through 7, indicating the associated
I/O bank.
If unused, these pins are in a high impedance state. |