Renesas M32R-FPU User Manual

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M32R-FPU Software Manual (Rev.1.01)

bit operation

INSTRUCTIONS

3.2 Instruction description

Bit operation for memory contents Set 0 to specified bit.

* ( signed char* ) ( Rsrc + ( signed short ) disp16 ) & = ~ ( 1<< ( 7-bitpos ) ) ;

BCLR reads the byte data in the memory at the address specified by the Rsrc combined with

the 16-bit displacement, and then stores the value of the bit that was specified by bitpos to be set

to “0”. The displacement is sign-extended before the address calculation. bitpos becomes 0 to 7;

MSB becomes 0 and LSB becomes 7. The memory is accessed in bytes. The LOCK bit is on

while the BCLR instruction is executed, and is cleared when the execution is completed. The

LOCK bit is internal to the CPU and cannot be directly read or written to by the user.

Condition bit C remains unchanged.

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 MCU.

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