EP3SE50F780I3N Altera, EP3SE50F780I3N Datasheet - Page 48

• Manufacturer Part Number: EP3SE50F780I3N
• Description: Stratix III
• Manufacturer: Altera

Adaptive Logic Modules
Figure 2–11. ALM in Arithmetic Mode
2–14
Stratix III Device Handbook, Volume 1
datae0
dataf1
dataf0
datae1
datac
datab
dataa
datad
While operating in arithmetic mode, the ALM can support simultaneous
use of the adder's carry output along with combinational logic outputs. In
this operation, the adder output is ignored. This usage of the adder with
the combinational logic output provides resource savings of up to 50% for
functions that can use this ability. An example of such functionality is a
conditional operation, such as the one shown in
4-Input
4-Input
4-Input
4-Input
LUT
LUT
LUT
LUT
carry_out
carry_in
adder0
adder1
D
D
reg0
reg1
Q
Q
Figure
To general or
To general or
To general or
To general or
local routing
local routing
local routing
local routing
Altera Corporation
2–12.
October 2007