8 extended transfer mode, Extended transfer mode -20, Address and size state calculations -20 – Motorola MPC8260 User Manual

Page 252: See section 8.4.3.8, òextended transfer mode

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8-20

MPC8260 PowerQUICC II UserÕs Manual

MOTOROLA

Part III. The Hardware Interface

8.4.3.8 Extended Transfer Mode

The MPC8260 supports an extended transfer mode that improves bus performance. This
should not be confused with the extended bus protocol used to support direct-store
operations supported in some earlier PowerPC processors. The MPC8260 can generate 5-,
6-, 7-, 16-, or 24-byte extended transfers. These transactions are compatible with the 60x

Table 8-10. Address and Size State Calculations

Size State

Address State [0Ð4]

Port Size

Next Size State

Next Address State [0Ð4]

Byte

x

x

x

x

x

x

Stop

2-Byte

x

x

x

x

0

Byte

Byte

x

x

x

x

1

x

x

0

0

1

Byte

x

x

0

1

0

x

x

1

0

1

Byte

x

x

1

1

0

x

x

x

0

1

Half

Byte

x

x

x

1

0

x

x

x

x

0

Stop

3-Byte

x

x

0

0

0

Byte

2-Byte

x

x

0

0

1

x

x

0

0

1

2-Byte

x

x

0

1

0

x

x

1

0

0

2-Byte

x

x

1

0

1

x

x

1

0

1

2-Byte

x

x

1

1

0

x

x

0

0

0

Half

Byte

x

x

0

1

0

x

x

0

0

1

2-Byte

x

x

0

1

0

x

x

1

0

0

Byte

x

x

1

1

0

x

x

1

0

1

2-Byte

x

x

1

1

0

x

x

x

x

x

Word

Stop

4-Byte

x

x

x

0

0

Byte

3-Byte

x

x

x

0

1

x

x

x

0

0

Half

2-Byte

x

x

x

1

0

x

x

x

x

x

Word

Stop

5-Byte

x

x

0

1

1

Byte

4-Byte

x

x

1

0

0

6-Byte

x

x

0

1

0

Byte

5-Byte

x

x

0

1

1

x

x

0

1

0

Half

4-Byte

x

x

1

0

0

7-Byte

x

x

0

0

1

Byte

6-Byte

x

x

0

1

0

8-Byte

x

x

0

0

0

Byte

7-Byte

x

x

0

0

1

x

x

0

0

0

Half

6-Byte

x

x

0

1

0

x

x

0

0

0

Word

4-Byte

x

x

1

0

0

x

x

0

0

0

Double

Stop

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