EP2SGX30CF780C5N Datasheet, PDF (56/316 Pages) Altera Corporation – Section I. Stratix II GX Device Data Sheet

Adaptive Logic Modules
Adaptive Logic
Modules
The basic building block of logic in the Stratix II GX architecture is the
ALM. The ALM provides advanced features with efficient logic
utilization. Each ALM contains a variety of look-up table (LUT)-based
resources that can be divided between two adaptive LUTs (ALUTs). With
up to eight inputs to the two ALUTs, one ALM can implement various
combinations of two functions. This adaptability allows the ALM to be
completely backward-compatible with four-input LUT architectures. One
ALM can also implement any function of up to six inputs and certain
seven-input functions.
In addition to the adaptive LUT-based resources, each ALM contains two
programmable registers, two dedicated full adders, a carry chain, a
shared arithmetic chain, and a register chain. Through these dedicated
resources, the ALM can efficiently implement various arithmetic
functions and shift registers. Each ALM drives all types of interconnects:
local, row, column, carry chain, shared arithmetic chain, register chain,
and direct link interconnects. Figure 2–35 shows a high-level block
diagram of the Stratix II GX ALM while Figure 2–36 shows a detailed
view of all the connections in the ALM.
Figure 2–35. High-Level Block Diagram of the Stratix II GX ALM
carry_in
shared_arith_in
reg_chain_in
dataf0
datae0
dataa
datab
datac
datad
datae1
dataf1
Combinational
Logic
adder0
adder1
DQ
reg0
DQ
reg1
carry_out
shared_arith_out
reg_chain_out
To general or
local routing
To general or
local routing
To general or
local routing
To general or
local routing
2–48
Stratix II GX Device Handbook, Volume 1
Altera Corporation
October 2007