MultiTrack Interconnect
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 and C16 interconnects for connections
from one row to another. Additionally, R4 interconnects can drive R24
interconnects.
Figure 4–8. R4 Interconnect Connections
Adjacent LAB can
Drive onto Another
LAB's R4 Interconnect
C4, C8, and C16
Column Interconnects (1)
R4 Interconnect
Driving Right
R4 Interconnect
Driving Left
LAB
Neighbor
Primary
LAB (2)
LAB
Neighbor
Notes to Figure 4–8:
(1) C4 interconnects can drive R4 interconnects.
(2) This pattern is repeated for every LAB in the LAB row.
The R8 interconnects span eight LABs, M512 or M4K RAM blocks, or DSP
blocks to the right or left from a source LAB. These resources are used for
fast row connections in an eight-LAB region. Every LAB has its own set
of R8 interconnects to drive either left or right. R8 interconnect
connections between LABs in a row are similar to the R4 connections
shown in Figure 4–8, with the exception that they connect to eight LABs
to the right or left, not four. Like R4 interconnects, R8 interconnects can
drive and be driven by all types of architecture blocks. R8 interconnects
can drive other R8 interconnects to extend their range as well as C8
interconnects for row-to-row connections. One R8 interconnect is faster
than two R4 interconnects connected together.
R24 row interconnects span 24 LABs and provide the fastest resource for
long row connections between LABs, TriMatrix memory, DSP blocks, and
IOEs. The R24 row interconnects can cross M-RAM blocks. R24 row
interconnects drive to other row or column interconnects at every fourth
4–12
Stratix GX Device Handbook, Volume 1
Altera Corporation
February 2005