Introduction

Hello. It's Tott.

During the previous exchange with the headmaster, I wondered if the PHY that can be used by the device was different, so I investigated.

Devices that support UniPHY and ALTMEMPHY

Headmaster: "ALTMEMPHY is a PHY before UniPHY was released, so the supported device generation is old."

* In the table above, U indicates UniPHY and A indicates ALTMEMPHY.
* The above table refers to the External Memory Interface Handbook.


Me: "Surely the Arria® II GX family before Arria® V only supports ALTMEMPHY! ! 』

The table also tells you which memory devices each FPGA device family supports.

Me: "How did you know right away that Cyclone® V is a device that supports UniPHY?"

Headmaster: "It's because ALTMEMPHY is grayed out on the IP selection screen of the Quartus® II MegaWizard Plug-In Manager."

Me: "Ah! It's true! PHYs and memory devices that can be selected by tools are limited! 』

While the tables in the External Memory Interface Handbook and the IP selection screens in the Quartus® II MegaWizard Plug - In Manager provide information on PHY and memory device support, there are tools available to examine memory interface performance.

It is the External Memory Interface Spec Estimator.

External Memory Interface Spec Estimator

■ This tool is available on Altera's website.
Go to the External Memory Interface Spec Estimator page and edit the filter items at the top of the page to specify the target device family and other conditions.

■ Then, the results of the External Memory Interface Spec Estimator will be displayed at the bottom of the page.

How to use the External Memory Interface Spec Estimator is next time! ! looking forward to.

Summary of this time

• ALTMEMPHY is a PHY before UniPHY was released, so the generation of devices that can be used is old.
• You can check whether the device supports UniPHY or ALTMEMPHY by referring to the table in the External Memory Interface Handbook or the IP selection screen of MegaWizard Plug - In Manager of Quartus® II.
• There is a tool (External Memory Interface Spec Estimator) on Altera's home page that can examine the performance of memory interfaces.