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2 memory data formats – Renesas H8S/2111B User Manual

Page 62

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Rev. 1.00, 05/04, page 28 of 544

2.5.2

Memory Data Formats

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.

7

0

7

6

5

4

3

2

1

0

MSB

LSB

MSB

MSB

LSB

LSB

Data Type

Address

1-bit data

Byte data

Word data

Address L

Address L

Address 2M

Address 2M + 1

Longword data

Address 2N

Address 2N + 1

Address 2N + 2

Address 2N + 3

Data Image

Figure 2.10 Memory Data Formats

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