ASR
SC140 DSP Core Reference Manual
A-57
ASR
Arithmetic Shift Right
ASR
By One Bit (DALU)
Description
Status and Conditions that Affect Instruction
Status and Conditions Changed by Instruction
Example
asr d5,d3
Operation
Assembler Syntax
Da>>1
→
Dn
ASR Da,Dn
ASR Da,Dn
Performs an arithmetic right shift by one bit on the source register Da, and stores it in the destination
register Dn. The LSB (bit 0) of the source register is copied into the status register carry (C) bit. Bits [39:1]
of the source register are copied into bits [38:0] of the destination register. Bit 39 of the source register is
copied into bit 39 of the destination register.
Register Address
Bit Name
Description
SR[2]
SM
If set, selects 32-bit arithmetic saturation mode.
SR[5:4]
S[1:0]
Scaling mode bits determine which bits in the result are used in the
Ln bit calculation.
Register Address
Bit Name
Description
SR[0]
C
Da[0] is stored in the carry bit.
Ln
L
If not in arithmetic saturation mode (SR [SM] = 0), calculates and
updates the Ln bit in the destination register. If in arithmetic
saturation mode (SR [SM] = 1), clears the Ln bit in the destination
register.
EMR[2]
DOVF
Set if the result cannot be represented in 40 bits, or if the result
saturates to 32 bits in arithmetic saturation mode.
Register/Memory Address
Before
After
D5
$00 0000 7903
L3:D3
$0:$00 0000 3C81
0
15
16
31
32
39
C
39
Summary of Contents for SC140 DSP Core
Page 12: ...xii SC140 DSP Core Reference Manual ...
Page 18: ...xviii SC140 DSP Core Reference Manual ...
Page 32: ...1 6 SC140 DSP Core Reference Manual Core Architecture Features ...
Page 180: ...4 70 SC140 DSP Core Reference Manual Trace Unit Registers ...
Page 250: ...6 70 SC140 DSP Core Reference Manual Programming Rules ...
Page 314: ...7 64 SC140 DSP Core Reference Manual NOP Definition ...
Page 463: ...DI SC140 DSP Core Reference Manual A 149 15 8 7 0 DI 1 1 4 1 0 0 1 1 1 1 1 0 1 1 1 1 1 0 1 ...
Page 478: ...A 164 SC140 DSP Core Reference Manual EI ...
Page 618: ...A 304 SC140 DSP Core Reference Manual MOVES 4F s15 sssssssssssssss Signed 15 bit offset ...
Page 638: ...A 324 SC140 DSP Core Reference Manual MPYR ...
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Page 758: ...I 10 Index ...
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