p2125vps20 Renesas Electronics Corporation., p2125vps20 Datasheet - Page 70

• Manufacturer Part Number: p2125vps20
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 2 CPU
2.5.2
Figure 2.10 shows the data formats in memory. The H8S/2000 CPU can access word data and
longword data in memory, but word or longword data must begin at an even address. If an attempt
is made to access word or longword data at an odd address, no address error occurs but the least
significant bit of the address is regarded as 0, so the access starts at the preceding address. This
also applies to instruction fetches.
When SP (ER7) is used as an address register to access the stack, the operand size should be word
size or longword size.
Rev. 1.00 Sep. 21, 2006 Page 32 of 658
REJ09B0310-0100
Memory Data Formats
Data Type
1-bit data
Byte data
Word data
Longword data
Figure 2.10 Memory Data Formats
Address L
Address L
Address 2M
Address 2M + 1
Address 2N
Address 2N + 1
Address 2N + 2
Address 2N + 3
Address
MSB
MSB
MSB
7
7
6
Data Image
5
4
3
2
1
LSB
LSB
LSB
0
0