I n t e g r a to r S e r i e s F P G A s : 1 2 0 0 X L a n d 3 2 0 0 D X F a m i l i e s
Lo g i c M o du le s
3200DX and 1200XL devices contain three types of logic
modules:
combinatorial
(C-modules),
sequential
(S-modules), and decode (D-modules). 1200XL devices
contain only the C-module and S-module, while the 3200DX
devices contain D-modules and dual-port SRAM modules in
addition to the S-module and C-module.
The C-module is shown in
and implements the
following function:
Y=!S1*!S0*D00+!S1*S0*D01+S1*!S0*D10+S1*S0*D11
where:
S0=A0*B0
S1=A1+B1
The S-module shown in
is designed to implement
high-speed sequential functions within a single logic
module. The S-module implements the same combinatorial
logic function as the C-module while adding a sequential
element. The sequential element can be configured as
either a D-type flip-flop or a transparent latch. To increase
flexibility, the S-module register can be bypassed so that it
implements purely combinatorial logic.
A0
B0
S0
D00
D01
D10
D11
S1
A1
B1
Y
Figure 1 •
C-Module Implementation
D00
D01
D10
D11
S1
Y
S0
CLR
D
Q
OUT
D00
D01
D10
D11
S1
Y
S0
D
GATE
Q
OUT
Up to 7-Input Function Plus D-Type Flip-Flop with Clear
Up to 7-Input Function Plus Latch
D00
D0
Y
D1
S
D
GATE
CLR
Q
OUT
D01
D10
D11
S1
S0
Y
OUT
Up to 4-Input Function Plus Latch with Clear
Up to 8-Input Function (Same as C-Module)
Figure 2 •
S-Module Implementation
6
Discontinued – v3.0
ACTEL [ Actel Corporation ]
