mc68hc908ap8a Freescale Semiconductor, Inc, mc68hc908ap8a Datasheet - Page 41

• Manufacturer Part Number: mc68hc908ap8a
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

2.4 Random-Access Memory (RAM)
Addresses $0060 through $085F (or $045F) are RAM locations. The location of the stack RAM is
programmable. The 16-bit stack pointer allows the stack to be anywhere in the 64k-byte memory space.
Within page zero are 160 bytes of RAM. Because the location of the stack RAM is programmable, all page
zero RAM locations can be used for I/O control and user data or code. When the stack pointer is moved
from its reset location at $00FF, direct addressing mode instructions can access efficiently all page zero
RAM locations. Page zero RAM, therefore, provides ideal locations for frequently accessed global
variables.
Freescale Semiconductor
For correct operation, the stack pointer must point only to RAM locations.
Priority
Highest
INT Flag
Table 2-1. Vector Addresses (Continued)
IF8
IF7
IF6
IF5
IF4
IF3
IF2
IF1
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MC68HC908AP A-Family Data Sheet, Rev. 3
Address
$FFEC
$FFED
$FFEE
$FFFC
$FFFD
$FFEF
$FFFA
$FFFB
$FFFE
$FFFF
$FFF0
$FFF1
$FFF2
$FFF3
$FFF4
$FFF5
$FFF6
$FFF7
$FFF8
$FFF9
NOTE
TIM2 Channel 1 Vector (High)
TIM2 Channel 1 Vector (Low)
TIM2 Channel 0 Vector (High)
TIM2 Channel 0 Vector (Low)
TIM1 Overflow Vector (High)
TIM1 Overflow Vector (Low)
TIM1 Channel 1 Vector (High)
TIM1 Channel 1 Vector (Low)
TIM1 Channel 0 Vector (High)
TIM1 Channel 0 Vector (Low)
PLL Vector (High)
PLL Vector (Low)
IRQ2 Vector (High)
IRQ2 Vector (Low)
IRQ1 Vector (High)
IRQ1 Vector (Low)
SWI Vector (High)
SWI Vector (Low)
Reset Vector (High)
Reset Vector (Low)
Vector
Random-Access Memory (RAM)
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