mc68ec060 Freescale Semiconductor, Inc, mc68ec060 Datasheet - Page 84

• Manufacturer Part Number: mc68ec060
• Description: Mc68060 Superscalar 68k Microprocessor Including The Lc060 And Ec060
• Manufacturer: Freescale Semiconductor, Inc

X—Motorola Reserved
4.2.3 Translation Table Example
Figure 4-12 illustrates an access example to the logical address $76543210 while in the
supervisor mode with an 8-Kbyte memory page size. The RI field of the logical address, $3B,
is mapped into bits 8–2 of the SRP value to select a 32-bit root table descriptor at a root-
level table. The selected root table descriptor points to the base of a pointer-level table, and
the PI field of the logical address, $15, is mapped into bits 8–2 of this base address to select
a pointer descriptor within the table. This pointer table descriptor points to the base of a
page-level table, and the PGI field of the logical address, $1, is mapped into bits 6–2 of this
base address to select a page descriptor within the table.
MOTOROLA
These bit fields are reserved for future use by Motorola.
SUPERVISOR
MODE
ADDRESS OFFSET =
TABLE ENTRY # =
$76543210 =
0 1 1 1 0 1 1 0 0 1 0 1 0 1 0 0 0 0 1 X X X X X X X X X X X X X
SRP
ROOT INDEX
Figure 4-12. Example Translation Table
$EC
$3B
$3B
M68060 USER’S MANUAL
ROOT LEVEL
POINTER INDEX
TABLE $00
$00001800
TABLES
$15
$54
LOGICAL ADDRESS
PAGE INDEX
$15
$01
$04
POINTER LEVEL
TABLE $3B
TABLE $00
$00003000
TABLE $7F
TABLES
Memory Management Unit
PAGE OFFSET
$01
FRAME ADDRESS
PAGE LEVEL
TABLE $15
TABLE $1F
TABLE $00
TABLES
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