SH7065 Datasheet, PDF (71/941 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7000 Series

Section 2 CPU
Single Data Addressing
DSP instructions include two single data transfer instructions (MOVS.W, MOVS.L) that load data
into, or store data from, a DSP register. With these instructions, one of registers R2 to R5 is used
as the single data transfer address register (As).
The following four kinds of addressing can be used with single data transfer instructions.
1. Non-update address register addressing:
The As register is an address pointer. It is not updated.
2. Addition index register addressing:
The As register is an address pointer. After a data transfer, the value of the Is register is added
to the As register (post-updating).
3. Increment address register addressing:
The As register is an address pointer. After a data transfer, the As register is incremented by 2
or 4 (post-updating).
4. Decrement address register addressing:
The As register is an address pointer. Before a data transfer, –2 or –4 is added to the As
register (i.e. 2 or 4 is subtracted) (pre-updating).
The R8 register is the index register (Is) for the address pointer (As). Single data transfer
addressing is shown in figure 2.10.
Rev. 5.00 Sep 11, 2006 page 49 of 916
REJ09B0332-0500