A logic option that specifies whether to target look-up table (LUT), Product Term, or ROM structures when implementing logic in the device—or whether to allow the Compiler to automatically choose whichever structures it finds to be most appropriate. The Technology Mapper option allows you to determine whether logic is implemented in Logic Array Blocks (LABs), Embedded Array Blocks (EABs), or Embedded System Blocks (ESBs). This option is available for ACEX® 1K, APEX™ 20K, APEX 20KC, APEX 20KE, APEX™ II, ARM®-based Excalibur™, FLEX 10KE, FLEX® 6000, and Mercury™ devices.
The following settings are available:
| Look-up Table (LUT) | Implements the entity in logic elements. |
| Product Term | Implements the entity in macrocells, that is, in embedded cells within an ESB set to use Product Term mode. This option is available for APEX 20K, and APEX II devices only. |
| Auto | Implements the entity using LUT, Product Term or ROM structures, and automatically chooses the best result. The criterion (area or speed) for choosing the best result is determined by the setting for the Optimization Technique option. This option is available for APEX 20K, and APEX II devices only. |
| ROM | Implements the entity in ROM mode, that is, in embedded cells within an EAB or ESB set to use ROM mode. This option is available for ACEX 1K, APEX 20K, APEX II, ARM-based Excalibur, FLEX 10KE, and Mercury devices only. |
This option is ignored if it is assigned to anything other than a design entity. Depending on the setting of this option, other logic options may also be ignored. For example, because carry and cascade chains can be implemented only in LUTs, the Auto Carry Chains and Auto Cascade Chains options are ignored if the Product Term or ROM setting is selected. Similarly, because parallel expanders can be implemented only in product terms, the Auto Parallel Expander Chains option is ignored if the LUT or ROM setting is selected.
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