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Texas Instruments MSP430x1xx User Manual

Page 55

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Data in the Memory

4-3

Memory

4.2

Data in the Memory

Bytes are located at even or odd addresses as shown in Figure 4–3. However,
words are only located at even addresses. Therefore, when using word
instructions, only even addresses may be used. The low byte of a word is
always at an even address. The high byte of a word is at the next odd address
after the address of the word. For example, if a data word is located at address
xxx2h, then the low byte of that data word is located at address xxx2h, and the
high byte of that word is located at address xxx3h.

Figure 4–3. Bits, Bytes, and Words in a Byte

-

Organized Memory

15

7

14

6

. . Bits . .

. . Bits . .

9

1

8

0

Byte

Byte

Word (High Byte)

Word (Low Byte)

xxxAh

xxx9h

xxx8h

xxx7h

xxx6h

xxx5h

xxx4h

xxx3h