Chapter 21 Interrupt (S12MC9S12XDP512V1)
MC9S12XDP512 Data Sheet, Rev. 2.11
854 PRELIMINARY Freescale Semiconductor
NON-DISCLOSURE AGREEMENT REQUIRED
Table 21-6. INT_CFDATA0–7 Field Descriptions
Field Description
7
RQST
XGATE Request Enable — This bit determines if the associated interrupt request is handled by the CPU or by
the XGATE module.
0 Interrupt request is handled by the CPU
1 Interrupt request is handled by the XGATE module
Note: The IRQ interrupt cannot be handled by the XGATE module. For this reason, the configuration register
for vector (vector base + 0x00F2) = IRQ vector address) does not contain a RQST bit. Writing a 1 to the
location of the RQST bit in this register will be ignored and a read access will return 0.
2–0
PRIOLVL[2:0]
Interrupt Request Priority Level Bits — The PRIOLVL[2:0] bits configure the interrupt request priority level of
the associated interrupt request. Out of reset all interrupt requests are enabled at the lowest active level (“1”)
to provide backwards compatibility with previous HCS12 interrupt controllers. Please also refer to Table 21-7 for
available interrupt request priority levels.
Note: Write accesses to configuration data registers of unused interrupt channels will be ignored and read
accesses will return all 0. For information about what interrupt channels are used in a specific MCU,
please refer to the Device User Guide of that MCU.
Note: When vectors (vector base + 0x00F0–0x00FE) are selected by writing 0xF0 to INT_CFADDR, writes to
INT_CFDATA2–7 (0x00F4–0x00FE) will be ignored and read accesses will return all 0s. The
corresponding vectors do not have configuration data registers associated with them.
Note: Write accesses to the configuration register for the spurious interrupt vector request
(vector base + 0x0010) will be ignored and read accesses will return 0x07 (request is handled by the
CPU, PRIOLVL = 7).
Table 21-7. Interrupt Priority Levels
Priority PRIOLVL2 PRIOLVL1 PRIOLVL0 Meaning
0 0 0 Interrupt request is disabled
low 0 0 1 Priority level 1
0 1 0 Priority level 2
0 1 1 Priority level 3
1 0 0 Priority level 4
1 0 1 Priority level 5
1 1 0 Priority level 6
high 1 1 1 Priority level 7