r5f71374an80fpv Renesas Electronics Corporation., r5f71374an80fpv Datasheet - Page 48

• Manufacturer Part Number: r5f71374an80fpv
• Description: 32-bit Risc Microcomputer Superh?? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

Section 2 CPU
2.3
2.3.1
The size of register operands is always longwords (32 bits). When loading byte (8 bits) or word
(16 bits) data in memory into a register, the data is sign-extended to longword and stored in the
register.
2.3.2
Memory data formats are classified into bytes, words, and longwords. Byte data can be accessed
from any address. Locate, however, word data at an address 2n, longword data at 4n. Otherwise,
an address error will occur if an attempt is made to access word data starting from an address other
than 2n or longword data starting from an address other than 4n. In such cases, the data accessed
cannot be guaranteed. The hardware stack area, pointed by the hardware stack pointer (SP, R15),
uses only longword data starting from address 4n because this area holds the program counter and
status register.
Rev. 1.00 Sep. 21, 2007 Page 22 of 1124
REJ09B0402-0100
Data Formats
Register Data Format
Memory Data Formats
Address 2n
Address 4n
31
Figure 2.3 Memory Data Format
Figure 2.2 Register Data Format
Address m
31
Byte
Word
Address m + 1
Longword
23
Byte
Longword
Address m + 2
15
Byte
Address m + 3
Word
7
Byte
0
0