MPC555
/
MPC556
BURST BUFFER
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
4-22
Table 4-6 MI_RA[0:3] Registers Bits Description
Bit(s)
Name
Description
0:19
RS
Region size. The region size is a power of two, determined as follows:
0000_0000_0000_0000_0000 — 4 Kbytes
0000_0000_0000_0000_0001 — 8 Kbytes
0000_0000_0000_0000_0011 — 16 Kbytes
0000_0000_0000_0000_0111 — 32 Kbytes
0000_0000_0000_0000_1111 — 64 Kbytes
0000_0000_0000_0001_1111 — 128 Kbytes
0000_0000_0000_0011_1111 — 256 Kbytes
0000_0000_0000_0111_1111 — 512 Kbytes
0000_0000_0000_1111_1111 — 1 Mbyte
0000_0000_0001_1111_1111 — 2 Mbytes
0000_0000_0011_1111_1111 — 4 Mbytes
0000_0000_0111_1111_1111 — 8 Mbytes
0000_0000_1111_1111_1111 — 16 Mbytes
0000_0001_1111_1111_1111 — 32 Mbytes
0000_0011_1111_1111_1111 — 64 Mbytes
0000_0111_1111_1111_1111 — 128 Mbytes
0000_1111_1111_1111_1111 — 256 Mbytes
0001_1111_1111_1111_1111 — 512 Mbytes
0011_1111_1111_1111_1111 — 1 Gbyte
0111_1111_1111_1111_1111 — 2 Gbytes
1111_1111_1111_1111_1111 — 4 Gbytes
20:31
PP
1
NOTES:
1. G and PP attributes perform similar protection activities on a region. The more protective attribute will be implied
on the region if the attributes programming oppose each other.
Protection bits:
00: Supervisor — No Access, User — No Access.
01: Supervisor — Fetch, User — No Access.
1x: Supervisor — Fetch, User — Fetch.
22:24
—
Reserved
25
G
Guard attribute for region
0 = Speculative fetch is not prohibited from region. Region is not guarded.
1 = Speculative fetch is prohibited from guarded region. An exception will occur under such at-
tempt.
26:27
CMPR
2
2. This bit is available only on the MPC556.
Compressed Region.
x0 = The region in not restricted.
01 = Region is considered a non-compressed code region. Access to the region is allowed only
in “Decompression Off” mode.
11 = Region is considered a compressed code region. Access to the region is allowed only in
“Decompression On” mode.
28:30
—
Reserved
F
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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