Stratix II Architecture
The DSP block is divided into four block units that interface with four
LAB rows on the left and right. Each block unit can be considered one
complete 18 × 18-bit multiplier with 36 inputs and 36 outputs. A local
interconnect region is associated with each DSP block. Like an LAB, this
interconnect region can be fed with 16 direct link interconnects from the
LAB to the left or right of the DSP block in the same row. R4 and C4
routing resources can access the DSP block's local interconnect region.
The outputs also work similarly to LAB outputs as well. Eighteen outputs
from the DSP block can drive to the left LAB through direct link
interconnects and eighteen can drive to the right LAB though direct link
interconnects. All 36 outputs can drive to R4 and C4 routing
interconnects. Outputs can drive right- or left-column routing.
Figures 2–29 and 2–30 show the DSP block interfaces to LAB rows.
Figure 2–29. DSP Block Interconnect Interface
DSP Block
OA[17..0]
OB[17..0]
R4, C4 & Direct
R4, C4 & Direct
Link Interconnects
Link Interconnects
A1[17..0]
B1[17..0]
OC[17..0]
OD[17..0]
A2[17..0]
B2[17..0]
OE[17..0]
OF[17..0]
A3[17..0]
B3[17..0]
OG[17..0]
OH[17..0]
A4[17..0]
B4[17..0]
Altera Corporation
May 2007
2–45
Stratix II Device Handbook, Volume 1
ALTERA [ ALTERA CORPORATION ]
