Texas Instruments TMS320C28x, Reference Manual

Page: 262 / 695

IMPYL ACC,XT,loc32
6-105
IMPYL ACC,XT,loc32 Signed 32 X 32-Bit Multiply (Lower Half)
SYNTAX OPTIONS OPCODE OBJMODE RPT CYC
IMPYL ACC,XT,loc32
0101 0110 0100 0100
0000 0000 LLLL LLLL
1 − 2
Operands ACC Accumulator register
XT Multiplicand register
loc32 Addressing mode (see Chapter 5)
Description Multiply the signed 32-bit content of the XT register by the signed 32-bit
content of the location pointed to by the “loc32” addressing mode and store
the lower 32 bits of the 64-bit result in the ACC register:
ACC = signed XT * signed [loc32];
Flags and Z After the operation, the Z flag is set if the ACC value is zero, else Z is cleared. g
Modes
N
After the operation, the N flag is set if bit 31 of the ACC is 1, else N is cleared.
Repeat This instruction is not repeatable. If this instruction follows the RPT
instruction, it resets the repeat counter (RPTC) and executes only once.
Example
; Calculate result: Y32 = M32*X32 + B32
MOVL XT,@M32 ; XT = M32
IMPYL ACC,XT,@X32 ; ACC = low 32 bits of (M32*X32)
ADDL ACC,@B32 ; ACC = ACC + B32
MOVL @Y32,ACC ; Store result into Y32