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Short Desc. : ALTMEMPHY (DDR3)
Overview :

1. About this Megafunction

This user guide is only for legacy designs as it describes the specifications and functional descriptions of the ALTMEMPHY megafunctions that are common to non-Altera PHY interface (nonAFI) variations. This user guide also describes the implementation of the QDR II+ and QDR II SRAM interfaces for legacy designs targeted for Arria® GX, Stratix® II, and Stratix II GX devices.

The ALTMEMPHY megafunction is an interface between a memory controller and memory devices and performs read and write operations to the memory. The megafunction is available as a stand-alone product or as an integrated product with Altera® high-performance memory controllers. As a stand-alone product, use the ALTMEMPHY megafunction with either custom or third-party controllers.

The ALTMEMPHY megafunction for DDR3, DDR2, and DDR SDRAM offers two different PHY-to-controller interfaces: Altera PHY interface (AFI) and nonAFI. The AFI is supported for all variations of ALTMEMPHY for DDR3, DDR2, and DDR SDRAM. ALTMEMPHY for DDR3 SDRAM only support the AFI. The AFI results in a simpler connection between the PHY and controller, so Altera recommends that you use the AFI for new designs; only use the nonAFI for legacy designs.

For information about using the external memory interfaces (DDR3, DDR2, and DDR SDRAM) with AFI and the ALTMEMPHY megafunction, refer to Volume 3: Implementing Altera Memory Interface IP of the External Memory Interface Handbook.

For more information about the ALTMEMPHY megafunction features, refer to Volume 3: Implementing Altera Memory Interface IP of the External Memory Interface Handbook.

For information about issues on the ALTMEMPHY megafunction in a particular Quartus® II software version, refer to the Quartus II Software Release Notes. This section describes the memory preset settings for the ALTMEMPHY (nonAFI) megafunction with the QDR II+/QDR II SRAM interfaces only. For information about using the MegaWizard™ Plug-In Manager or the SOPC Builder flow to implement the ALTMEMPHY megafunction, refer to the Getting Started chapter in Volume 3: Implementing Altera Memory Interface IP of the External Memory Interface Handbook.

The ALTMEMPHY Parameter Settings page in the ALTMEMPHY MegaWizard interface (Figure 2-1) allows you to parameterize the following settings:

  • Memory Settings
  • PHY Settings
  • Controller Interface Settings

Note: The options for PHY Settings tab are editable if they apply to the Altera device that you have chosen for your interface. Otherwise, the options are disabled. The options for Controller Interface Settings tab are disabled when you are creating an ALTMEMPHY (nonAFI) megafunction for QDR II+/QDR II SRAM interface.

For more information about the PHY Settings and the Controller Interface Settings, refer to the Parameter Settings chapter in Volume 3: Implementing Altera Memory Interface IP of the External Memory Interface Handbook

Figure 2–1. ALTMEMPHY Parameter Settings Page



The text window at the bottom of the MegaWizard Plug-In Manager displays information about the memory interface, warnings (for example, if you are creating an interface above the maximum frequency supported), and errors if you are trying to create something that is not supported. The Finish button is disabled until you fix all the errors indicated in this window.

The following section describes the Memory Settings tab for QDR II+/QDR II SRAM interface in more detail.

Memory Settings

In the Memory Settings tab, you can choose the frequency of operation for the device and a particular memory device for your system. Under General Settings, you can choose the device family, speed grade, and clock information. In the middle of the page (left-side), you can filter the available memory device listed on the right side of the Memory Presets dialog box, refer to Figure 2–1. If you cannot find the exact device that you are using, choose a device that has the closest specifications, then manually modify the parameters to match your actual device by clicking Modify parameters, next to the Selected memory preset field. Table 2–1 describes the General Settings available on the Memory Settings page of the ALTMEMPHY MegaWizard interface. Table 2–1. General Settings

Parameter Name Description
Device family Targets device family. The device family selected here must match the device family selected on MegaWizard page 2a.
Speed grade Selects a particular speed grade of the device (for example, 2, 3, or 4 for the Stratix III device family).
PLL reference clock frequency Determines the clock frequency of the external input clock to the PLL. Ensure that you use three decimal points if the frequency is not a round number (for example, 166.667 MHz or 100 MHz) to avoid a functional simulation or a PLL locking issue.
Memory clock frequency Determines the memory interface clock frequency. If you are operating a memory device below its maximum achievable frequency, ensure that you enter the actual frequency of operation rather than the maximum frequency achievable by the memory device. Also, ensure that you use three decimal points if the frequency is not a round number (for example, 333.333 MHz or 400 MHz) to avoid a functional simulation or a PLL locking issue.
Controller data rate Selects the data rate for the memory controller. Sets the frequency of the controller to equal to either the memory interface frequency (full-rate) or half of the memory interface frequency (half-rate).
Local interface clock frequency This field’s value depends on the memory clock frequency and controller data rate, and whether or not you turn on the Enable Half Rate Bridge option.
Local interface width This field’s value depends on the memory clock frequency and controller data rate, and whether or not you turn on the Enable Half Rate Bridge option.

Table 2–2 describes the options available to filter the Memory Presets that are displayed. This section is where you indicate that you are creating a datapath for QDR II+/QDR II SRAM.

Table 2–2. Memory Presets List

Parameter Name Description
Memory type You can filter the type of memory to display. For the ALTMEMPHY megafunction with nonAFI, select QDR II+ SRAM and QDR II SRAM.
Memory vendor You can filter the memory types by vendor. JEDEC is also one of the options, allowing you to choose the JEDEC specifications. If your chosen vendor is not listed, you can choose Other for QDR II+/QDR II SRAM interfaces. Then, pick a device that has similar specifications to your chosen device and check the values of each parameter. Make sure you change the each parameter value to match your device specifications.
Memory format You can filter the type of memory by format (for example, components or DIMM packages). This option is only available for DDR3, DDR2, and DDR SDRAM interfaces.
Maximum frequency You can filter the type of memory by the maximum operating frequency.

Use the Preset Editor to Create a Custom Memory Preset

Pick a device in the Memory Presets list that is closest or the same as the actual memory device that you are using. Then, click the Modify Parameters button to parameterize the following settings in the Preset Editor dialog box:

  • Memory attributes—These are the settings that determine your system's number of DQ, DQS, address, and memory clock pins.
  • Memory initialization options—These settings are stored in the memory mode registers as part of the initialization process.
  • Memory timing parameters—These are the parameters that create and time-constraint the PHY.

Note: Even though the device you are using is listed in Memory Presets, ensure that the settings in the Preset Editor dialog box are accurate as some parameters may have been updated in the memory device datasheets.

You can change the parameters with a white background to reflect your system. You can also change the parameters with a gray background so the device parameters match the device you are using. These parameters in gray background are characteristics of the chosen memory device and changing them creates a new custom memory preset. If you click Save As (at the bottom left of the page) and save the new settings in the <quartus_install_dir>\quartus\common\ip\altera\altmemphy\lib\ directory, you can use this new memory preset in other Quartus II projects created in the same version of the software.

When you click Save, the new memory preset appears at the bottom of the Memory Presets list in the Memory Settings tab.

Note: If you save the new settings in a directory other than the default directory, click Load Preset in the Memory Settings tab to load the settings into the Memory Presets list.

QDR II+/QDR II SRAM Preset Editor Page

Figure 2–2 shows the Preset Editor page for the ALTMEMPHY variation for QDR II+/QDR II SRAM interfaces.

Figure 2–2. Preset Editor for QDR II+/QDR II SRAM Interfaces




Categories :
Portability :
 FPGA Technologis 
Altera :
Arria II GX
HardCopy II
HARDCOPY III
HARDCOPY IV GX
Stratix II
Stratix II GX
STRATIX III E
STRATIX IV GT
STRATIX IV GX

Type : Hard
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