Renesas SuperH SH-4A - MOVA (Move Effective Address): Data Transfer Instruction

Rev. 1.50, 10/04, page 275 of 448
10.1.34 MOVA (Move Effective Address): Data Transfer Instruction
Format Operation Instruction Code Cycle T Bit
MOVA
@(disp*,PC),R0
disp × 4 + PC &
H'FFFFFFFC + 4 → R0
11000111dddddddd 1 —
Note: * The assembler of Renesas Technology uses the value after scaling (×1, ×2, or ×4) as
the displacement (disp).
Description: This instruction stores the source operand effective address in general register R0.
The 8-bit displacement is multiplied by four after zero-extension. The PC value is the address of
this instruction, but a value with the lower 2 bits adjusted to B'00 is used in address calculation.
Notes: If this instruction is executed in a delay slot, a slot illegal instruction exception will be
generated.
Operation:
MOVA(int d) /* MOVA @(disp,PC),R0 */
{
unsigned int disp;
disp = (unsigned int)(0x000000FF & d);
R[0] = (PC&0xFFFFFFFC) + 4 + (disp<<2);
PC += 2;
}
Example:
Address .org H'1006
1006 MOVA STR*,R0 ;STR address → R0
1008 MOV.B @R0,R1 ;R1 = “X” ← Position after adjustment of lower 2 bits of PC
100A ADD R4,R5
.align 4
100C STR:.sdata "XYZP12"
Note: * The assembler of Renesas Technology uses the value after scaling (×1, ×2, or ×4) as
the displacement (disp).
Possible Exceptions:
• Slot illegal instruction exception