Honored Contributor
Honored ContributorCyclone HMC only support full-rate and this cannot be change. However, the HMC have the multiport front end component between the controller and user logic and this MPFE is allow lower frequency than full rate.
See the Multi-Port Front End (MPFE) section of this document for details. https://www.altera.com/documentation/hco1416493470528.html#hco1416493209306 focus on this paragraph: The fabric interface provides communication between the Avalon-ST-like internal protocol of the hard memory interface and the external Avalon-MM protocol. The fabric interface supports frequencies in the range of 10 MHz to one-half of the memory interface frequency. For example, for an interface running at 533 MHz, the maximum user logic frequency is 267 MHz. The MPFE handles the clock crossing between user logic and the hard memory interface. (This message was posted on behalf of Intel Corporation)
