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Honored ContributorCyclone V: max speed TTL parallel bus on GPIO
Hello! I want to make a high speed 14-bit wide parallel bus (TTL levels) on Cyclone V. What max speed it can be? For example 250 MHz??? I don't have this devise, so i can't test it myself. So...
Altera_ForumHonored Contributor
Honored Contributor --- Quote Start --- Hello! I want to make a high speed 14-bit wide parallel bus (TTL levels) on Cyclone V. What max speed it can be? For example 250 MHz??? I don't have this devise, so i can't test it myself. Sorry for my english... --- Quote End --- This is device and layout dependent. You're going to want to check the Cyclone V data sheet and decide on the desired speed grade. Also, you're looking at LVTTL, not TTL. I'd even recommend using LVCMOS to minimize drive current. The faster you go, the more important timing constraints are. You'll want to read the guides on source-synchronous timing (AN433 and "Source-Synchronous Timing with TimeQuest" by Ryan Scoville)
