The Cyclone® IV GX clock networks have been modified from the Cyclone® III to have up to thirty global clock networks feeding the FPGA fabric for devices offered in the F484 package and larger. Smaller devices have up to twenty global clock networks. As with the Cyclone® III, the GCLK I/O can be used as general purpose I/O and are highly recommended for use for high fanout signals such as resets or clock enables. Again, as mentioned previously, the MPLLs and GPLLs can be shared.