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Instructions
MPYF32 RdH, ReH, RfH
MOV32 RaH, mem32
32-bit Floating-Point Multiply with Parallel Move
Operands
RdH
floating-point destination register for the MPYF32 (R0H to R7H)
RdH cannot be the same register as RaH
ReH
floating-point source register for the MPYF32 (R0H to R7H)
RfH
floating-point source register for the MPYF32 (R0H to R7H)
RaH
floating-point destination register for the MOV32 (R0H to R7H)
RaH cannot be the same register as RdH
mem32
pointer to a 32-bit memory location. This will be the source of the MOV32.
Opcode
LSW: 1110 0011
0000 fffe
MSW: eedd daaa
mem32
Description
Multiply the contents of two floating-point registers and load another.
RdH = ReH * RfH
RaH = [mem32]
Restrictions
The destination register for the MPYF32 and the MOV32 must be unique. That is, RaH
cannot be the same register as RdH.
Flags
This instruction modifies the following flags in the STF register:.
Flag
TF
ZI
NI
ZF
NF
LUF
LVF
Modified
No
Yes
Yes
Yes
Yes
Yes
Yes
The STF register flags are modified as follows:
•
LUF = 1 if MPYF32 generates an underflow condition.
•
LVF = 1 if MPYF32 generates an overflow condition.
The MOV32 Instruction will set the NF, ZF, NI and ZI flags as follows:
NF = RaH(31);
ZF = 0;
if(RaH(30:23) == 0) { ZF = 1; NF = 0; }
NI = RaH(31);
ZI = 0;
if(RaH(31:0) == 0) ZI = 1;
Pipeline
MPYF32 takes 2 pipeline-cycles (2p) and MOV32 takes a single cycle. That is:
MPYF32
RdH, ReH, RfH
; 2 pipeline cycles (2p)
||
MOV32
RaH, mem32
; 1 cycle
; <-- MOV32 completes, RaH updated
NOP
; 1 cycle delay or non-conflicting instruction
; <-- MPYF32 completes, RdH updated
NOP
Any instruction in the delay slot must not use RdH as a destination register or as a
source operand.
SPRUEO2A – June 2007 – Revised August 2008
Instruction Set
107
Summary of Contents for TMS320C28 series
Page 2: ...2 SPRUEO2A June 2007 Revised August 2008 Submit Documentation Feedback ...
Page 12: ...Introduction 12 SPRUEO2A June 2007 Revised August 2008 Submit Documentation Feedback ...
Page 20: ...CPU Register Set 20 SPRUEO2A June 2007 Revised August 2008 Submit Documentation Feedback ...
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