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Intel STRONGARM SA-1100 User Manual

Page 51

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SA-1100 Developer’s Manual

5-7

Coprocessors

5.2.12

Register 13 – Process ID Virtual Address Mapping

The SA-1100 supports the remapping of virtual addresses through a process ID (PID) register. The
6-bit PID value is OR’ed with bits 30..25 of the virtual address when bits 31..25 of the virtual
address are zero. This effectively remaps the address to one of 64 “slots” in the lower 2 Gbyte
address space. The following table shows the OPC_2 and CRm field encodings used to access the
process ID register. This register is zero at reset and if left unmodified, effectively disables the
remapping function. As such, no explicit enable or disable function is necessary. Reserved bits read
as zero and must be written as zero. This register is readable and writable.

The following figure shows the format of the process ID register.

Function

OPC_2

CRm

Access process ID register

0b000

0b0000

0

24

31

25

30

Process ID

Reserved

r