Renesas M32R-FPU Manual Do Utilizador

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M32R-FPU Software Manual (Rev.1.01)

load/store instruction

Store unlocked

if ( LOCK == 1 ) { * ( int *) Rsrc2 = Rsrc1; }

LOCK = 0;

When the LOCK bit is 1, the contents of Rsrc1 are stored at the memory location specified by

Rsrc2. When the LOCK bit is 0, store operation is not executed. The condition bit (C) is un-

changed.

This instruction clears the LOCK bit to 0 in addition to the simple storage operation.

The LOCK bit is internal to the CPU and cannot be accessed except by using the LOCK and

UNLOCK instructions.

The user cannot directly read or write to this bit.

The LOCK bit is internal to the CPU and is the control bit for receiving all bus right requests

from circuits other than the CPU.

Refer to the Users Manual for non-CPU bus right requests, as the handling differs according to

the type of M

Address exception (AE)

INSTRUCTIONS

3.2 Instruction description