VI SDRAM CONTROLLER BLOCK: SDRAM INTERFACE

A-1

Memory Configuration

Use the registers described below to select the area in which SDRAMs are connected and the chip enable output pin to be used for SDRAMs.

Selecting areas

Area 7 or 13: SDRAR0 (D7)/SDRAM area configuration register (0x39FFC0)

Area 8 or 14: SDRAR1 (D6)/SDRAM area configuration register (0x39FFC0)

Writing "1" to SDRARx sets the corresponding area for SDRAM use. When SDRARx = "0" (default), the area is used for devices other than SDRAM that are controlled only by the BCU.

Selecting chip enable

#SDCE0(#CE7/13): SDRPC0 (D3)/SDRAM area configuration register (0x39FFC0)

#SDCE1(#CE8/14): SDRPC1 (D2)/SDRAM area configuration register (0x39FFC0)

Writing "1" to SDRPCx sets the corresponding pin for SDRAM chip enable output. When SDRPCx = "0" (default), the pin is used for devices other than SDRAM that are controlled only by the BCU.

Although #SDCE0 and #SDCE1 are assigned to the #CE7 and #CE8 pins, respectively, they are not necessarily fixed to either area. For example, even when using area 7 or 13 for SDRAMs, the chip enable used for the SDRAM can be #SDCE1 (#CE8/14).

Table 2.5 lists the chip enable address ranges and the SDRAM sizes that can be connected when the area(s) and chip enable are selected according to the above.

 

 

 

Table 2.5

Chip Enable Configuration

 

 

CEFUNC

SDRAR0

SDRAR1

SDRPC0

 

SDRPC1

#SDCE0

#SDCE1

SDRAM size

 

address range

address range

(16-bit)

 

 

 

 

 

 

XX

0

0

X

 

X

N/A

N/A

0

X

X

0

 

0

N/A

N/A

0

 

 

 

1

0

1

 

0

Area 7

N/A

2MB

 

1

0

0

 

1

N/A

Area 7

2MB

 

1

0

1

 

1

Area 7

N/A

2MB

00

0

1

1

 

0

Area 8

N/A

2MB

0

1

0

 

1

N/A

Area 8

2MB

(default)

 

0

1

1

 

1

N/A

Area 8

2MB

 

 

 

1

1

1

 

0

Area 7&8

N/A

4MB

 

1

1

0

 

1

N/A

Area 7&8

4MB

 

1

1

1

 

1

Area 7

Area 8

2MB x 2

 

1

0

1

 

0

Area 13

N/A

16MB

 

1

0

0

 

1

N/A

Area 13

16MB

 

1

0

1

 

1

Area 13

N/A

16MB

01

0

1

1

 

0

Area 14

N/A

16MB

10

0

1

0

 

1

N/A

Area 14

16MB

11

0

1

1

 

1

N/A

Area 14

16MB

 

1

1

1

 

0

Area 13&14

N/A

32MB

 

1

1

0

 

1

N/A

Area 13&14

32MB

 

1

1

1

 

1

Area 13

Area 14

16MB x 2

Area 7 = 0x400000–0x5FFFFF, Area 8 = 0x600000–0x7FFFFF, Area 7&8 = 0x400000–0x7FFFFF

Area 13 = 0x2000000–0x2FFFFFF, Area 14 = 0x3000000–0x3FFFFFF, Area 13&14 = 0x2000000–0x3FFFFFF

B-VI

SDRAM

S1C33L03 FUNCTION PART

EPSON

B-VI-2-7