www.ti.com

Peripheral Architecture

Figure 14. DDR2 SDRAM Column, Row, and Bank Access

Bank 0

Row 0

Row 1

Row 2

Row N

 

C

C C

C

 

o

o

o

o

 

l

l

l

l

0

1

2

3

M

 

 

C C C

C

 

 

o

o

o

o

 

 

l

l

l

l

Bank 1

0

1

2

3

M

Row 0

 

 

 

 

 

Row 1

 

 

 

 

 

Row 2

 

 

 

 

 

Row N

 

 

 

 

 

 

 

C

C C

C

 

 

o

o

o

o

 

 

l

l

l

l

Bank 2

0

1

2

3

M

Row 0

 

 

 

 

 

Row 1

 

 

 

 

 

Row 2

 

 

 

 

 

Row N

 

 

 

 

 

 

 

C C C

C

 

 

o

o

o

o

 

 

l

l

l

l

Bank P

0

1

2

3

M

Row 0

 

 

 

 

 

Row 1

 

 

 

 

 

Row 2

 

 

 

 

 

Row N

 

 

 

 

 

AM is number of columns (as determined by PAGESIZE) minus 1, P is number of banks (as determined by IBANK) minus 1, and N is number of rows (as determined by both PAGESIZE and IBANK) minus 1.

2.7DDR2 Memory Controller Interface

To move data efficiently from on-chip resources to external DDR2 SDRAM device, the DDR2 memory controller makes use of a command FIFO, a write FIFO, a read FIFO, and command and data schedulers. Table 6 describes the purpose of each FIFO.

Figure 15 shows the block diagram of the DDR2 memory controller FIFOs. Commands, write data, and read data arrive at the DDR2 memory controller parallel to each other. The same peripheral bus is used to write and read data from external memory as well as internal memory-mapped registers.

Table 6. DDR2 Memory Controller FIFO Description

 

 

Depth (64-Bit

FIFO

Description

Doublewords)

Command

Stores all commands coming from on-chip requestors

7

Write

Stores write data coming from on-chip requestors to

11

 

memory

 

Read

Stores read data coming from memory to on-chip

17

 

requestors

 

22

DSP DDR2 Memory Controller

SPRUF85 –October 2007

 

 

Submit Documentation Feedback

Page 22
Image 22
Texas Instruments TMS320C6452 DSP manual DDR2 Memory Controller Interface, DDR2 Memory Controller Fifo Description