mc9s12e256 Freescale Semiconductor, Inc, mc9s12e256 Datasheet - Page 506

• Manufacturer Part Number: mc9s12e256
• Description: Hcs12 Microcontrollers 16-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Chapter 17 Interrupt (INTV1)
17.3.2.3
Read: Anytime
Write: Only if I mask in CCR = 1
17.4
The interrupt sub-block processes all exception requests made by the CPU. These exceptions include
interrupt vector requests and reset vector requests. Each of these exception types and their overall priority
level is discussed in the subsections below.
17.4.1
The INT does not contain any user-controlled options for reducing power consumption. The operation of
the INT in low-power modes is discussed in the following subsections.
17.4.1.1
The INT does not contain any options for reducing power in run mode.
17.4.1.2
Clocks to the INT can be shut off during system wait mode and the asynchronous interrupt path will be
used to generate the wake-up signal upon recognition of a valid interrupt or any XIRQ request.
17.4.1.3
Clocks to the INT can be shut off during system stop mode and the asynchronous interrupt path will be
used to generate the wake-up signal upon recognition of a valid interrupt or any XIRQ request.
506
PSEL[7:1]
Reset
Field
7:1
W
R
Functional Description
PSEL7
Low-Power Modes
Highest Priority I Interrupt Select Bits — The state of these bits determines which I-bit maskable interrupt will
be promoted to highest priority (of the I-bit maskable interrupts). To promote an interrupt, the user writes the least
significant byte of the associated interrupt vector address to this register. If an unimplemented vector address or
a non I-bit masked vector address (value higher than 0x00F2) is written, IRQ (0xFFF2) will be the default highest
priority interrupt.
Highest Priority I Interrupt (Optional)
Operation in Run Mode
Operation in Wait Mode
Operation in Stop Mode
1
7
= Unimplemented or Reserved
PSEL6
Figure 17-5. Highest Priority I Interrupt Register (HPRIO)
1
6
Table 17-4. HPRIO Field Descriptions
PSEL5
MC9S12E256 Data Sheet, Rev. 1.08
1
5
PSEL4
1
4
Description
PSEL3
3
0
PSEL2
0
2
Freescale Semiconductor
PSEL1
1
1
0
0
0