12 memory map, 12 memory map -18 – Intel PXA255 User Manual

Page 48

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2-18

Intel® PXA255 Processor Developer’s Manual

System Architecture

2.12

Memory Map

Figure 2-2

and

Figure 2-3

show the full processor memory map.

Any unused register space from 0x4000_0000 to 0x4BFF_FFFF is reserved.

Note: Accessing reserved portions of the memory map will give unpredictable results.

The PCMCIA interface is divided into Socket 0 and Socket 1 space. These two sockets are each

subdivided into I/O, memory and attribute space. Each socket is allocated 256 MB of memory

space.

[4]

Static Memory Control Pins: During Sleep Mode, these pins can be programmed to either drive the value in the
Sleep State Register or to be placed in Hi-Z. To select the Hi-Z state, software must set the FS bit in the Power
Manager General Configuration Register. If PCFR[FS] is not set, then during the transition to sleep these pins
function as described in [3], above. For nWE, nOE, and nCS[0], if PCFR[FS] is not set, they are driven high by
the Memory Controller before entering sleep. If PCFR[FS] is set, these pins are placed in Hi-Z.

[5]

PCMCIA Control Pins: During Sleep Mode: Can be programmed either to drive the value in the Sleep State
Register or to be placed in Hi-Z. To select the Hi-Z state, software must set PCFR[FP]. If it is not set, then during
the transition to sleep these pins function as described in [3], above.

[6]

During sleep, this supply may be driven low. This supply must never be high impedance.

[7]

Remains powered in sleep mode.

Table 2-7. Pin Description Notes (Sheet 2 of 2)

Note

Description

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