EPM570 Altera, EPM570 Datasheet - Page 20

• Manufacturer Part Number: EPM570
• Description: MAX II Device Family
• Manufacturer: Altera

Logic Elements
Figure 2–9. Carry Select Chain
2–14
MAX II Device Handbook, Volume 1
LAB Carry-In
A1
B1
A2
B2
A3
B3
A4
B4
A5
B5
A6
B6
A7
B7
A8
B8
A9
B9
A10
B10
LAB Carry-Out
0
0
LE0
LE1
LE2
LE3
LE4
LE5
LE6
LE7
LE8
LE9
1
1
Sum1
Sum2
Sum3
Sum4
Sum5
Sum6
Sum7
Sum8
Sum9
Sum10
The Quartus II software automatically creates carry chain logic during
design processing, or the designer can create it manually during design
entry. Parameterized functions such as LPM functions automatically take
advantage of carry chains for the appropriate functions. The Quartus II
software creates carry chains longer than 10 LEs by linking adjacent LABs
within the same row together automatically. A carry chain can extend
horizontally up to one full LAB row, but they do not extend between LAB
rows.
To top of adjacent LAB
Core Version a.b.c variable
LAB Carry-In
Carry-In0
Carry-In1
data1
data2
Carry-Out0
LUT
LUT
LUT
LUT
Carry-Out1
Altera Corporation
December 2004
Sum