XC4000FM Datasheet, PDF (15/40 Pages) Xilinx, Inc – Flexible function generators

G4
G3
LOGIC
FUNCTION
OF
G'
G2
G1-G4
G1
F4
F3
LOGIC
FUNCTION
OF
F'
F2
F1-F4
F1
K
(CLOCK)
C1
C2
H1
DIN
DIN
F'
G'
H'
C3
C4
S/R
EC
S/R
CONTROL
SD
D
Q
YQ
LOGIC
FUNCTION
OF _H'
F', G',
AND
H1
G'
H'
DIN
F'
G'
H'
1
S/R
CONTROL
EC
RD
Y
SD
D
Q
XQ
EC
RD
1
H'
F'
X
MULTIPLEXER CONTROLLED
BY CONFIGURATION PROGRAM
Figure 13. Simplified Block Diagram of XC4000 Configurable Logic Block
X1519
A1 G4
G3
G2
B1 G1
CIN 1
CIN 2
M
F4
F3
B0 F2
A0 F1
COUT
Logic
Function
of G1 - G4
G'
SUM 1
Carry
Logic
Carry
Logic
Logic
Function
of F1 - F4
F'
SUM 0
X5373
Figure 14. Fast Carry Logic in Each CLB
C1
C2
C3
C4
WE(S/R) D1(H1) D0(DIN)
EC
G4
WE
DATA
IN
G3
G'
Function
G2
Generator
G1
M
Write G'
M
Write F'
M
16 x 2
F4
WE
DATA
IN
F3
F'
Function
F2
Generator
F1
M Configuration Memory Bit
Figure 15. CLB Function Generators Can Be Used as
Read/Write Memory Cells
X6074
2-21