Texas Instruments TMS320C28x, Reference Manual

Page: 290 / 695

LSL ACC,#1..16
6-133
LSL ACC,#1..16 Logical Shift Left
SYNTAX OPTIONS OPCODE OBJMODE RPT CYC
LSL ACC,#1..16
1111 1111 0011 SHFT
X Y N+1
Operands ACC Accumulator register
#1..16 Shift value
Description Perform a logical shift left on the content of the ACC register by the amount
specified by the shift value. During the shift, the low order bits of the ACC
register are zero filled and the last bit shifted out is stored in the carry flag bit:
0
C
ACC
ACC
Last bit out
Discard
other bits
Left shift
(Immediate value)
Flags and
Modes
N After the shift, if bit 31 of ACC is 1 then the negative flag bit is set; otherwise it
is cleared.
Z After the shift, if ACC is 0, then the Z bit is set, otherwise it is cleared.
C The last bit to be shifted out of ACC is stored in C.
Repeat This instruction is repeatable. If the operation follows a RPT instruction, then
the LSL instruction will be executed N+1 times. The state of the Z, N, and C
flags will reflect the final result.
Example
; Logical shift left contents of VarA by 4:
MOVL ACC,@VarA ; ACC = VarA
LSL ACC,#4 ; Logical shift left ACC by 4
MOVL @VarA,ACC ; Store result into VarA