MC68030RC33C Freescale Semiconductor, MC68030RC33C Datasheet - Page 115

• Manufacturer Part Number: MC68030RC33C
• Description: IC MPU 32BIT ENHANCED 128-PGA
• Manufacturer: Freescale Semiconductor

Specifications of MC68030RC33C

• Processor Type: M680x0 32-Bit
• Speed: 33MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 128-PGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -

3
3-30
3.5.2 Nested Subroutine Calls
The LINK instruction pushes an address onto the stack, saves the stack ad-
dress at which the address is stored, and reserves an area of the stack. Using
this instruction in a series of subroutine calls results in a linked list of stack
frames.
The UNLK instruction removes a stack frame from the end of the list by
from the stack. When the operand of the instruction is the address of the link
address at the bottom of a stack frame, the effect is to remove the stack
frame from the stack and from the linked list.
loading an address into the stack pointer and pulling the value at that address
AFTER DELETING ENTRY:
OOELETE
DOLOOP
OOEMPTY
ODOONE
BEFORE DELETING ENTRY:
LISTPUT J
CLB.L
CAS2.L
BNE
BRA
CAS2.L
BNE
LEA
LEA
MOVE.L
BEQ
MOVE.L
BEQ
LEA
LIST__PUT,AO
LIST_GET. A1
(A1),O }
DODONE
(LAST,O1),D2
DDEMPTY
(NEXT. D2),A2
DO
Dl:O1,D2:DO,(A1):(A2)
DDLOOP
DDDONE
DI:D1,D2:D2,(A1):(AO)
DDLOOP
Figure 3-5. Doubly Linked List Deletion
LIST_PUT
MC68030 USER'S MANUAL
IF BOTH POINTERS STILL POINT TO THIS ENTRY, UPDATE THEM
IF NOT. TRY AGAIN
IF STILL FIRST ENTRY, SET HEAD AND TAIL POINTERS TO NULL
IF NOT, TRY AGAIN
SUCCESSFUL ENTRY DELETION, ADDRESS OF DELETED ENTRY IN Ol (MAY BE NULL)
GET ADDRESS OF HEAD POINTER IN AO
GET ADDRESS OF TAIL POINTER IN A1
MOVE TAIL POINTER INTO 01
IF NO LIST. QUIT
PUT BACKWARO POINTER IN D2
IF ONLY ONE ELEMENT. UPDATE POINTERS
PUT AODRESS OF FORWARD POINTER IN A2
PUT NULL POINTER VALUE IN DO
~
LIST_GET
LIST_G ET - ~
~
MOTOROLA
DELETED ENTRY
1