Subah, Subtract using halfword addressing mode subah – Texas Instruments TMS320C67X/C67X+ DSP User Manual
Page 315
Subtract Using Halfword Addressing Mode
SUBAH
3-255
Instruction Set
SPRU733
Subtract Using Halfword Addressing Mode
SUBAH
Syntax
SUBAH (.unit) src2, src1, dst
.unit = .D1 or .D2
Compatibility
C62x, C64x, C67x, and C67x+ CPU
Opcode
31
29
28
27
23
22
18
17
13
12
7
6
5
4
3
2
1
0
creg
z
dst
src2
src1
op
1 0 0 0 0 s p
3
1
5
5
5
6
1
1
Opcode map field used... For operand type...
Unit
Opfield
src2
src1
dst
sint
sint
sint
.D1, .D2
11 0101
src2
src1
dst
sint
ucst5
sint
.D1, .D2
11 0111
Description
src1 is subtracted from src2 using the halfword addressing mode specified for
src2. The subtraction defaults to linear mode. However, if src2 is one of A4−A7
or B4−B7, the mode can be changed to circular mode by writing the appropri-
ate value to the AMR (see section 2.7.3, page 2-10). src1 is left shifted by 1.
The result is placed in dst.
Execution
if (cond)
src2 −a src1
→
dst
else nop
Pipeline
Stage
E1
Read
src1, src2
Written
dst
Unit in use
.D
Instruction Type
Single-cycle
Delay Slots
0
See Also
SUB, SUBAB, SUBAW
Pipeline