Describes the features and characteristics of Altera's Double Data Rate I/O (ALTDDIO_IN, ALTDDIO_OUT, and ALTDDIO_BIDIR) Megafunctions
This document provides a user guide for the Double Data Rate I/O (DDR I/O) megafunctions: ALTDDIO_IN, ALTDDIO_OUT, and ALTDDIO_BIDIR. These megafunctions configure DDR I/O registers in various Altera device series, including APEX II, Arria, Cyclone, HardCopy, and Stratix. They are designed to implement interfaces for DDR inputs, outputs, and bidirectional data transfer.
| Supported Device Families | APEX II, Arria, Cyclone, HardCopy, and Stratix |
|---|---|
| Interface Types | DDR SDRAM, DDR2 SDRAM, RLDRAM II, QDR SRAM, QDRII SRAM |
| Data Capture/Transmission | Both edges of the reference clock |
They implement interfaces for DDR inputs, DDR outputs, and bidirectional DDR inputs and outputs, respectively.
They can be parameterized using the MegaWizard Plug-In Manager or the command-line interface (CLI).