3
3-66 M32R-FPU Software Manual (Rev.1.01)

LDUBLDUB

load/store instruction

Load unsigned byte

[Mnemonic]
(1) LDUB Rdest,@Rsrc
(2) LDUB Rdest,@(disp16,Rsrc)
[Function]
Load to register from the contents of the memory.
(1) Rdest = *( unsigned char *) Rsrc;
(2) Rdest = *( unsigned char *) ( Rsrc + ( signed short ) disp16 );
[Description]
(1) LDUB zero-extends the byte data from the memory at the address specified by Rsrc and
loads it into Rdest.
(2) LDUB zero-extends the byte data of the memory at the address specified by Rsrc com-
bined
with the 16-bit displacement, and loads it into Rdest.
The displacement value is sign-extended to 32 bits before address calculation.
The condition bit (C) is unchanged.
[EIT occurrence]
None
[Encoding]
dest1010
dest0010 1001 src
1001 src
LDUB Rdest,@Rsrc
LDUB Rdest,@(disp16,Rsrc)
disp16
INSTRUCTIONS
3.2 Instruction description