FAQ

Where do I find information for:FPGA library elements and the input/output port list for each?Constraints that can be applied to my design after my design is synthesized? Synthesis constraints that can be applied to my design?

You can use the ispLEVER help menu to find:

• FPGA Library elements
• FPGA Library black-box prototypes
• FPGA design constraints
• Synthesis design constraints
  

You can access the help menu:

1. Open up ispLEVER
2. Click on "Help" -> "ispLEVER Help".
3. Your default web browser will launch, and the ispLever Online Help page will be displayed. The Contents tab for the left hand pane is active.
   

A useful feature, available in the online help, is the Search option. This allows you to find topics that guide you to content to answer your question.

To find the list of FPGA Library Elements:

1. Click on the Contents tab in the left hand pane, if it is not active.
2. Click on the FPGA Libraries Guide hyperlink. This expands the section making a list of FPGA device families visible.
   
3. Select the FPGA family you are want more information about. A list of general logic categories is made available.
   
4. Please note that some of the special cells in the I/O blocks (IDDR and ODDR) are not listed in the PIC Cells link, but in the Special Cells link.

To find the black-box prototypes for the library elements:

1. Click on the Contents tab in the left hand pane, if it is not active.
   
2. Click on "Design Flow User Guide" -> "Design Entry" -> "HDL Design" -> "Designing with Lattice Library Elements" document.
3. Click on the Lattice Synthesis Header Libraries link in the right hand pane. This opens up a guide on where to find the instantiation examples for the library elements. All example instantiations are located at <ispLEVER_install_dir>/cae_library/synthesis/verilog/<architecture>.v and <ispLEVER_install_dir>/cae_library/synthesis/vhdl/<architecture>.vhd

To find the list of FPGA design constraints:

1. Click on the Contents tab in the left hand pane, if it is not active.
2. Click on "Constraints Reference Guide" link.
3. Click on the "Preferences" hyperlink. This will bring up the list of constraints, with hyperlinks for each constraint to take you to an example and explanation of that constraint.

To find synthesis constraints, there are two ways to do it:

1. Click on the Contents tab in the left hand pane, if it is not active.
2. Click on the "Introduction to ispLEVER Documentation"
3. In the right pane click on the "Synplify and Synplify Pro for Lattice Reference Manual" link.
4. This will open the Synplify reference manual. If you click on the Synthesis Attributes and Directives bookmark in the PDF manual then Summary of Attributes and Directives in the manual, you will be brought to a list of attributes.

You can also open up Synplify stand alone to get to the documents.

1. Go to ispLEVER and click on the red Synplify icon. You can also use the "Tools" -> "Synplify Pro Synthesis" menu item.
   
2. When Synplify starts, click on "Help" -> "Help". This will bring up the Synplify online help. Select the Search tab.
3. Search for syn_*. This will return a list of synthesis attributes, as well other documents relevant to using synthesis constraints.