MultiTrack Interconnect
The R4 interconnects span four LABs and are used for fast row
connections in a four-LAB region. Every LAB has its own set of R4
interconnects to drive either left or right. Figure 2–10 shows R4
interconnect connections from an LAB. R4 interconnects can drive and be
driven by row IOEs. For LAB interfacing, a primary LAB or horizontal
LAB neighbor can drive a given R4 interconnect. For R4 interconnects that
drive to the right, the primary LAB and right neighbor can drive on to the
interconnect. For R4 interconnects that drive to the left, the primary LAB
and its left neighbor can drive on to the interconnect. R4 interconnects can
drive other R4 interconnects to extend the range of LABs they can drive.
R4 interconnects can also drive C4 interconnects for connections from one
row to another.
Figure 2–10. R4 Interconnect Connections
Adjacent LAB can
drive onto another
LAB’s R4 Interconnect
R4 Interconnect
Driving Right
C4 Column Interconnects (1)
R4 Interconnect
Driving Left
LAB
Neighbor
Primary
LAB (2)
LAB
Neighbor
Notes to Figure 2–10:
(1) C4 interconnects can drive R4 interconnects.
(2) This pattern is repeated for every LAB in the LAB row.
2–16Core Version a.b.c variable
MAX II Device Handbook, Volume 1
Altera Corporation
March 2008
ALTERA [ ALTERA CORPORATION ]
