Instantiating LPM & Other Parameterized Functions in Concept Schematics
You can use library of parameterized modules (LPM) functions and other
Altera®-provided parameterized functions in Concept schematics if you also use the HDL Direct utility.
To instantiate LPM functions, go through the following steps:
- Choose the Add Part button from the toolbar or type
add from the Concept window to open the Component Browser window.
- Choose alt_lpm (Library menu). All functions in the alt_lpm library are
MAX+PLUS® II-compatible. Choose Megafunctions/LPM from the MAX+PLUS II Help menu to get detailed information on all supported parameterized functions.
- Type
attribute, then click on each component to set parameters for each function. See General Guidelines below for additional information.
- Add
inport and outport symbols from the hdl_direct_lib library to the interface signals. Use the supply_0 and supply_1 symbols from the
hdl_direct_lib library to connect a net to GND or VCC.
- Continue with the steps necessary to complete your Concept schematic, as described in Creating Concept Schematics for Use with MAX+PLUS II Software.
Installing the Altera-provided MAX+PLUS II/Cadence interface on your computer automatically creates the following sample Concept schematic file, which includes LPM function instantiation:
- If a pin is not used, leave it floating. The concept2alt utility removes all unconnected pins when it generates an EDIF netlist file.
- For the
csfifo function, the value of the LPM_NUMWORDS parameter must be between
2LPM_WIDTHAD-1 and 2LPM_WIDTHAD.
- Make sure that any hexadecimal (Intel-format) file (.hex) that you use to specify the initial content of a memory does not have the same name as the design file name.
- Make sure that all properties and value strings are in uppercase letters, except the filename specified with the
LPM_FILE property, which should use the actual case of the filename.
- Choose the Set button in the Concept window and choose CAPS_LOCK_OFF for the CAPS LOCK option.
- Only the
LPM_POLARITY parameter (which can be set to INVERT or NORMAL) can determine the polarity of the bus or pin. You can display a bubble in the Concept schematic to indicate an inverted pin by typing BUBBLE in the Concept command window and selecting the appropriate pin. However, the bubble does not determine the polarity of the pin or bus.
- Avoid using the Replace button in the Concept window to replace old symbols with new ones: you may accidentally set unwanted properties. Instead, you should use the Delete button to delete old symbols and the Add button to add new symbol(s).
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