epm2210gm100i Altera Corporation, epm2210gm100i Datasheet - Page 20

• Manufacturer Part Number: epm2210gm100i
• Description: Section I. Max Ii Device Family Data Sheet
• Manufacturer: Altera Corporation

Logic Elements
Figure 2–8. LE in Dynamic Arithmetic Mode
Note to
(1)
2–12Core Version a.b.c variable
MAX II Device Handbook, Volume 1
LAB Carry-In
Carry-In0
Carry-In1
The addnsub signal is tied to the carry input for the first LE of a carry chain only.
data1
data2
data3
(LAB Wide)
Figure
addnsub
2–8:
(1)
Carry-Out0
The other two LUTs use the data1 and data2 signals to generate two
possible carry-out signals: one for a carry of 1 and the other for a carry of
0. The carry-in0 signal acts as the carry-select for the carry-out0
output and carry-in1 acts as the carry-select for the carry-out1
output. LEs in arithmetic mode can drive out registered and unregistered
versions of the LUT output.
The dynamic arithmetic mode also offers clock enable, counter enable,
synchronous up/down control, synchronous clear, synchronous load,
and dynamic adder/subtractor options. The LAB local interconnect data
inputs generate the counter enable and synchronous up/down control
signals. The synchronous clear and synchronous load options are
LAB-wide signals that affect all registers in the LAB. The Quartus II
software automatically places any registers that are not used by the
counter into other LABs. The addnsub LAB-wide signal controls
whether the LE acts as an adder or subtractor.
LUT
LUT
LUT
LUT
Carry-Out1
Register chain
connection
clock (LAB Wide)
(LAB Wide)
ena (LAB Wide)
aclr (LAB Wide)
sload
(LAB Wide)
Register Feedback
sclear
(LAB Wide)
ADATA
ENA
D
ALD/PRE
aload
CLRN
Q
Altera Corporation
Row, column, and
direct link routing
Row, column, and
direct link routing
Local routing
LUT chain
connection
Register
chain output
March 2008