EP3SE50F780I3N Altera, EP3SE50F780I3N Datasheet - Page 139

• Manufacturer Part Number: EP3SE50F780I3N
• Description: Stratix III
• Manufacturer: Altera

Altera Corporation
October 2007
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output_round
Table 5–9. DSP Block Dynamic Signals (Part 1 of 2)
signa
signb
Signal Name
You can use the rounding and saturation function described above in
regular supported multiplication operations as specified in
However, for accumulation type operations, the following convention is
used.
The functionality of the round logic unit is in the format of:
Result = RND[
operation.
Likewise, the functionality of the saturation logic unit is in the format of:
Result = SAT[
operation.
If both the round and saturation logic units are used for an accumulation
type of operation, the format is:
Result = SAT[RND[
DSP Block Control Signals
The Stratix III DSP block is configured using a set of static and dynamic
signals. The DSP block dynamic signals are user configurable and can be
set to toggled or not at run time. This list of dynamic signals is shown in
Table 5–9
Signed/unsigned control for all multipliers and adders.
signa
multiplier.
signb
multiplier.
signa
signa
signa
signa
Round control for first stage round/saturation block.
output_round
output_round
for “multiplier” input bus
= 1,
= 1,
= 0,
= 0,
for “multiplicand” input bus to
for the DSP block.
signb
signb
signb
signb
Σ
Σ
(A × B)], when used for an accumulation type of
= 1 for rounding on multiply output
= 0 for normal multiply output
(A × B)], when used for an accumulation type of
= 1 for signed-signed multiplication
= 0 for signed-unsigned multiplication
= 1 for unsigned-signed multiplication
= 0 for unsigned-unsigned multiplication
Σ
(A × B)]]
Function
datab[17:0]
dataa[17:0]
Stratix III Device Handbook, Volume 1
DSP Blocks in Stratix III Devices
to each
each
Table
Count
2
1
5–2.
5–39