Instructions
www.ti.com
RESTORE
Restore the Floating-Point Registers
Operands
none
This instruction does not have any operands
Opcode
LSW: 1110 0101
0110 0010
Description
Restore the floating-point register set (R0H - R7H and STF) from their shadow registers.
The SAVE and RESTORE instructions should be used in high-priority interrupts. That is
interrupts that cannot themselves be interrupted. In low-priority interrupt routines the
floating-point registers should be pushed onto the stack.
Restrictions
The RESTORE instruction cannot be used in any delay slots for pipelined operations.
Doing so will yield invalid results. To avoid this, the proper number of NOPs or
non-pipelined instructions must be inserted before the RESTORE operation.
; The following is INVALID
MPYF32
R2H, R1H, R0H
; 2 pipeline-cycle instruction (2p)
RESTORE
; INVALID, do not use RESTORE in a delay slot
; The following is VALID
MPYF32
R2H, R1H, R0H
; 2 pipeline-cycle instruction (2p)
NOP
; 1 delay cycle, R2H updated after this instruction
RESTORE
; VALID
Flags
Restoring the status register will overwrite all flags:
Flag
TF
ZI
NI
ZF
NF
LUF
LVF
Modified
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Pipeline
This is a single-cycle instruction.
Instruction Set
114
SPRUEO2A – June 2007 – Revised August 2008
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 ...
Page 136: ...Instruction Set 136 SPRUEO2A June 2007 Revised August 2008 Submit Documentation Feedback ...