mc68ec060 Freescale Semiconductor, Inc, mc68ec060 Datasheet - Page 80

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

MOTOROLA
ABBREVIATIONS:
NOTE :
EXIT TABLE SEARCH
RETURN
THE U-BIT OCCURS AFTER THE READ OF
THE NEXT LEVEL DESCRIPTOR.
DUE TO ACCESS PIPELINING, A POINTER
DESCRIPTOR WRITE ACCESS TO UPDATE
WP – ACCUMULATED WRITE-
V – LOGICAL "OR" OPERATOR
– ASSIGNMENT OPERATOR
Figure 4-9. Detailed Flowchart of Descriptor Fetch Operation
PROTECTION STATUS
'INVALID'
WRITE ACCESS
(SEE NOTE)
SCHEDULE
WRITE ACCESS (U
IF SCHEDULED, EXECUTE
(INDEX = RI, PI, OR PGI)
U
PREVIOUS DESCRIPTOR
AT PA = TA + (INDEX*4)
FETCH DESCRIPTOR
OTHERWISE
TYPE = 'PAGE' OR 'POINTER'
U = 0
1
(SEE NOTE)
WP = WP V W
'RESIDENT'
RETURN
U = 1
1) FOR
'POINTER'
UPDATE HISTORY AND STATUS
TYPE =
M68060 USER’S MANUAL
OF ALL BUS TRANSFERS
FETCH DESCRIPTOR &
NORMAL TERMINATION
U = 1
READ ACCESS
TYPE = 'PAGE'
OR 'INDIRECT'
TYPE = 'INDIRECT'
U = 0
PA = DESCRIPTOR ADDRESS
FETCH DESCRIPTOR AT
RMW ACCESS
WP = WP V W
EXECUTE
'RESIDENT'
LOCKED
U
OF ALL BUS TRANSFERS
NORMAL TERMINATION
(WP = 1 OR M = 1)
1
U = 0 &
WRITE ACCESS
RETURN
OR 'INDIRECT'
'INVALID'
WRITE ACCESS
WP = 0 & M = 0
U
EXECUTE
OTHERWISE
1, M
Memory Management Unit
RETURN
(WP = 1 OR M = 1)
1
U = 1 &
EXIT TABLE SEARCH
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