MC68030RC25C Freescale Semiconductor, MC68030RC25C Datasheet - Page 381

• Manufacturer Part Number: MC68030RC25C
• Description: IC MPU 32BIT ENHANCED 128-PGA
• Manufacturer: Freescale Semiconductor

Specifications of MC68030RC25C

• Processor Type: M680x0 32-Bit
• Speed: 25MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 128-PGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -

9
9-80
/* Block not found so find upper level entry unallocated and call SearchPageTable that will 'expand' */
/* Scan table pointed to by upper level index to see if it can hold the block. If not, see if it can be
/* be expanded. If successful then set flags in the page entries, set status to "OK" and User's
/* virtual address
Status = "Out of virtual Memory";
/* Scan User eligible page tables
for Upper_Table_Index = 1 to 31 do
/* the null table to hold the block.
for Upper_Table_Index = 1 to 31
/* No more virtual space, exit leaving Status = "out of virtual memory"
Declare NumPages;
if SizelnBytes > 16 megabytes then exit Vallocate;
NumPages = (SizelnBytes+PageSize-1)/PageSize;
exit Vallocate;
Declare Upper_Table Index, Lower Level_Index;
Procedure SearchPageTable;
Declare Maxfound;
Maxfound = 0;
For Lower_Level_Index = 0 to UppeLTable[].Lim]LField
If Upper_Table[].Status = allocated then call SearchPageTable;
If Status = "OK" then Exit Vallocate;
end;
]f Upper_Table[].Status = unallocated then call
/* count consecutive free pages until Maxfound met or not
If Lower_Table[].Status = invalid_unallocated then do
if Maxfound >= NumPages then do
Maxfound = Maxfound+l;
MC68030 USER'S M A N U A L
SearchPageTable;
/* number of pages required to hold request
/* default result status to this error
/* Pages needed
/*table indexes
/* Count of consecutive free blocks found
M O T O R O L A
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