EP2AGZ225HF40I3N Datasheet, PDF (103/382 Pages) Altera Corporation – Volume 1: Device Interfaces and Integration

Chapter 4: DSP Blocks in Arria II Devices
Arria II Operational Mode Descriptions
4–27
Figure 4–19 shows the shift mode configuration.
Figure 4–19. Shift Operation Mode Shown for Half-DSP Block
clock[3..0]
ena[3..0]
aclr[3..0]
signa
signb
rotate
shift_right
dataa_0[35..18]
datab_0[35..18]
+
dataa_0[17..0]
datab_0[35..18]
dataa_0[35..18]
32
+
result[ ]
datab_0[17..0]
+
dataa_0[17..0]
datab_0[17..0]
Half-DSP Block
Table 4–5 lists examples of shift operations.
Table 4–5. Examples of Shift Operations
Example
Logical Shift Left
LSL[N]
Logical Shift Right
LSR[32-N]
Arithmetic Shift Left
ASL[N]
Arithmetic Shift Right
ASR[32-N]
Rotation ROT[N]
Signa
Unsigned
Unsigned
Signed
Signed
Unsigned
Signb
Unsigned
Unsigned
Unsigned
Unsigned
Unsigned
Shift
0
1
0
1
0
Rotate
0
0
0
0
1
A-input
0×AABBCCDD
0×AABBCCDD
0×AABBCCDD
0×AABBCCDD
0×AABBCCDD
B-input
0×0000100
0×0000100
0×0000100
0×0000100
0×0000100
Result
0×BBCCDD00
0×000000AA
0×BBCCDD00
0×FFFFFFAA
0×BBCCDDAA
December 2010 Altera Corporation
Arria II Device Handbook Volume 1: Device Interfaces and Integration