MC68030RC25C Freescale Semiconductor, MC68030RC25C Datasheet - Page 83

• 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: -

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2.8.2 User P r o g r a m S t a c k s
To implement stack growth from high to low memory, use:
The user can implement stacks with the address register indirect with post-
For this type of stack, after either a push or a pull operation, register An
points to the top item on the stack. This is illustrated as:
To implement stack growth from low to high memory, use:
memory, aligning the stack pointer on a long-word address significantly
increment and predecrement addressing modes. With address register An
(n =0-6), the user can implement a stack that is filled either from high to low
memory or from low to high memory. Important considerations are:
increases the efficiency of stacking exception frames, subroutine calls and
returns, and other stacking operations.
• Use the predecrement mode to decrement the register before its contents
• Use the postincrement mode to increment the register after its contents
• Maintain the stack pointer correctly when byte, word, and long-word
(An)+ to pull data from the stack.
- ( A n ) to push data on the stack,
- ( A n ) to pull data from the stack.
(An)+ to push data on the stack,
are used as the pointer to the stack.
are used as the pointer to the stack.
items are mixed in these stacks.
An
MC68030 USER'S MANUAL
BOSOM OF STACK
HIGH MEMORY
LOW MEMORY
TOP OF STACK
(FREE)
MOTOROLA