Quartus II Settings File Reference Manual - Altera

4–18 Chapter 4: Analysis & Synthesis Assignments
AUTO_CARRY_CHAINS
AUTO_CARRY_CHAINS
Type
Allows the Compiler to create carry chains automatically by inserting CARRY_SUM
buffers into the design. This option is also required to recognize carry chains in any
design containing MAX+PLUS II-style CARRY buffers. The length of the chains is
controlled with the Carry Chain Length option. If this option is turned off, CARRY
buffers are ignored, but CARRY_SUM buffers are unaffected. The Auto Carry Chains
option is ignored if you select Product Term or ROM as the setting for the Technology
Mapper option.
This option is turned on by default.
Boolean
Device Support
This setting can be used in projects targeting the following device families:
■ Arria GX
■ Arria II GX
■ Arria II GZ
■ Arria V
■ Cyclone
■ Cyclone II
■ Cyclone III
■ Cyclone III LS
■ Cyclone IV E
■ Cyclone IV GX
■ Cyclone V
■ HardCopy II
■ HardCopy III
■ HardCopy IV
■ MAX II
■ MAX V
■ Stratix
■ Stratix GX
■ Stratix II
■ Stratix II GX
■ Stratix III
■ Stratix IV
Quartus Settings File June 2012 Altera Corporation
Reference Manual