To access this dialog, from the Edit menu, choose I/O Bank Settings.
Use this dialog to assign I/O technologies to I/O banks in ProASIC3 devices.
Choose Bank
Choose a bank from the drop-down menu. If you do not assign I/O standards to a bank, that bank uses the default standard selected in the Device Selection Wizard.
Select all technologies that the bank should support
Selecting an I/O standard selects all compatible standards and grays out incompatible ones. For example, selecting LVTTL also selects PCI, PCIX, and LVPECL, since they all have the same VCCI. Further, selecting GTLP (3.3V) disables SSTL3 as an option because the VREFs of the two are not the same.
VCCI
Each I/O bank has a common supply voltage, VCCI, for the I/Os within that bank.
Click Apply to assign the selected I/O standards to the selected bank. Any previously assigned I/Os in the bank that are no longer compatible with the standards applied are unassigned.