MultiTrack Interconnect
R24 row interconnects span 24 LABs and provide the fastest resource for
long row connections between non-adjacent LABs, M4K memory blocks,
dedicated multipliers, and row IOEs. R24 row interconnects drive to
other row or column interconnects at every fourth LAB. R24 row
interconnects drive LAB local interconnects via R4 and C4 interconnects
and do not drive directly to LAB local interconnects. R24 interconnects
can drive R24, R4, C16, and C4 interconnects.
Column Interconnects
The column interconnect operates similar to the row interconnect. Each
column of LABs is served by a dedicated column interconnect, which
vertically routes signals to and from LABs, M4K memory blocks,
embedded multipliers, and row and column IOEs. These column
resources include:
■
■
Register chain interconnects within an LAB
C4 interconnects traversing a distance of four blocks in an up and
down direction
■
C16 interconnects for high-speed vertical routing through the device
Cyclone II devices include an enhanced interconnect structure within
LABs for routing LE output to LE input connections faster using register
chain connections. The register chain connection allows the register
output of one LE to connect directly to the register input of the next LE in
the LAB for fast shift registers. The Quartus II Compiler automatically
takes advantage of these resources to improve utilization and
performance. Figure 2–9 shows the register chain interconnects.
2–12
Cyclone II Device Handbook, Volume 1
Altera Corporation
February 2007
ALTERA [ ALTERA CORPORATION ]
