XP2 Datasheet, PDF (23/92 Pages) Lattice Semiconductor – LatticeXP2 Family Data Sheet

Lattice Semiconductor
Architecture
LatticeXP2 Family Data Sheet
• In the ‘Signed/Unsigned’ options the operands can be switched between signed and unsigned on every cycle.
• In the ‘Add/Sub’ option the Accumulator can be switched between addition and subtraction on every cycle.
• The loading of operands can switch between parallel and serial operations.
MULT sysDSP Element
This multiplier element implements a multiply with no addition or accumulator nodes. The two operands, A and B,
are multiplied and the result is available at the output. The user can enable the input/output and pipeline registers.
Figure 2-20 shows the MULT sysDSP element.
Figure 2-20. MULT sysDSP Element
Shift Register B In
Multiplicand
m
Shift Register A In
m
Multiplier
n
n
n
Input Data
Register B
n
m
Input Data
m
Register A
n
m
Multiplier
x
m+n
(default)
Pipeline
Register
m+n
Output
Signed A
Signed B
Input
Register
Input
Register
To
Multiplier
To
Multiplier
CLK (CLK0,CLK1,CLK2,CLK3)
CE (CE0,CE1,CE2,CE3)
RST(RST0,RST1,RST2,RST3)
Shift Register B Out
Shift Register A Out
2-20