Intel PXA255 manual Boot-Time Configurations, Sxcnfg

Models: PXA255

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Memory Controller

6.10.2.2Boot-Time Configurations

The boot time configurations are shown in Figure 6-33- Figure 6-35. A boot from a single 32-Mbit SMROM with nWORD = 1 is not supported.

Three Configuration registers are affected at reset - MSC0:RBW0, MDREFR:E0PIN/K0RUN, and

SXCNFG.

Figure 6-33. Asynchronous Boot Time Configurations and Register Defaults

BOOT_SEL[2:0] = 000

 

 

 

 

 

 

MSC0

0x7FF0_7FF0

 

32

Asynchronous

RBW0 = 0

 

 

 

32-bit

 

 

 

 

 

 

 

 

 

ROM

SXCNFG

0x0004_0004

 

 

 

MDREFR

0x03CA_4FFF

 

 

 

E0PIN = 0, K0RUN = 0

 

 

BOOT_SEL[2:0] = 001

 

 

 

 

 

 

MSC0

0x7FF0_7FF8

 

16

Asynchronous

RBW0 = 1

 

 

 

 

16-bit

 

 

 

 

 

ROM

SXCNFG

0x0004_0004

 

 

 

MDREFR

0x03CA_4FFF

 

 

 

E0PIN = 0, K0RUN = 0

 

 

 

 

BOOT_SEL[2:0] = 000

SXMRS

0000_0000

 

 

BOOT_SEL[2:0] = 000

SXMRS

0000_0000

6-76

Intel® PXA255 Processor Developer’s Manual

Page 258
Image 258
Intel PXA255 manual Boot-Time Configurations, Sxcnfg