EP2AGX95EF29C6N Datasheet, PDF (103/380 Pages) Altera Corporation – 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
Signa
Signb Shift Rotate
A-input
B-input
Result
Logical Shift Left
Unsigned Unsigned
0
LSL[N]
0
0×AABBCCDD 0×0000100 0×BBCCDD00
Logical Shift Right _{Unsigned Unsigned}
1
LSR[32-N]
0
0×AABBCCDD 0×0000100 0×000000AA
Arithmetic Shift Left _{Signed Unsigned}
0
ASL[N]
0
0×AABBCCDD 0×0000100 0×BBCCDD00
Arithmetic Shift Right _{Signed Unsigned}
1
ASR[32-N]
0
0×AABBCCDD 0×0000100 0×FFFFFFAA
Rotation ROT[N] Unsigned Unsigned 0
1
0×AABBCCDD 0×0000100 0×BBCCDDAA
December 2010 Altera Corporation
Arria II Device Handbook Volume 1: Device Interfaces and Integration