EtronTech

EM68916DVAA

Etron Confidential

8

Rev. 1.0

Apr. 2009

Burst Mode Operation

Burst Mode operation is used to provide a constant flow of data to memory locations (write cycle) or from

memory locations (read cycle). There are two parameters that define how the Burst Mode operates. These

parameters include Burst Type and Burst Length and are programmed by addresses A0~A3 during the

Mode Register Set command. Burst Type is used to define the sequence in which the burst data will be

delivered from or stored to the DDR SDRAM. Two types of burst sequences are supported, Sequential and

Interleaved. See the table below. The Burst Length controls the number of bits that will be output after a read

command, or the number of bits to be input after a write command. The Burst Length can be programmed to

have a value of 2, 4, or 8.

Table 5.Burst Definition

Start Address

Burst

Length

A3

A2

A1

A0

Sequential

Interleave

X

X

X

0

0,1

0,1

2

X

X

X

1

1,0

1,0

X

X

0

0

0, 1, 2, 3

0, 1, 2, 3

X

X

0

1

1, 2, 3, 0

1, 0, 3, 2

X

X

1

0

2, 3, 0, 1

2, 3, 0, 1

4

X

X

1

1

3, 0, 1, 2

3, 2, 1, 0

X

0

0

0

0, 1, 2, 3, 4, 5, 6, 7

0, 1, 2, 3, 4, 5, 6, 7

X

0

0

1

1, 2, 3,4, 5, 6, 7, 0

1, 0, 3, 2, 5, 4, 7, 6

X

0

1

0

2, 3, 4, 5, 6, 7, 0, 1

2, 3, 0, 1, 6, 7, 4, 5

X

0

1

1

3, 4, 5, 6, 7, 0, 1, 2

3, 2, 1, 0, 7, 6, 5, 4

X

1

0

0

4, 5, 6, 7, 0, 1, 2, 3

4, 5, 6, 7, 0, 1, 2, 3

X

1

0

1

5, 6, 7, 0, 1, 2, 3, 4

5, 4, 7, 6, 1, 0, 3, 2

X

1

1

0

6, 7, 0, 1, 2, 3, 4, 5

6, 7, 4, 5, 2, 3, 0, 1

8

X

1

1

1

7, 0, 1, 2, 3, 4, 5, 6

7, 6, 5, 4, 3, 2, 1, 0