User I/O and Clock Pins

The following table lists the unused I/O and clock pins in a SmartFusion2/IGLOO2 device.

Table 1. Recommendations for Unused I/O and Clock Pins
I/O	Unused Condition	Remarks
MSIO	Libero-Defined DNC¹	Internal weak pull-up is available
MSIOD
DDRIO
Programming SPI pins
Crystal oscillator pins	Must be left floating and must not connect to ground (VSS)	Internal weak nominal 50 kΩ pull-up to VPP

Note:

1.Libero configures unused user I/O (MSIO, MSIOD, and DDRIO) as: input buffer disabled, output buffer tristated with weak pull-up.