Texas Instruments TMS320C67X/C67X+ DSP - 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