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Interrupts and Interrupt Controller (INTC)
PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor
10-5
Figure 10-4. Z0 Software Vector Mode: Interrupt Exception Handler Address Calculation
Figure 10-5. Z6 Software Vector Mode: Interrupt Exception Handler Address Calculation
, the common interrupt exception handler reads the INTC_IACKR_PRC
n
to
determine the vector of the interrupt request source. The INTC_IACKR_PRC
n
register contains a 32-bit
address for a vector table base address (VTBA) plus an offset to access the interrupt vector (INTVEC).
The address is then used to branch to the corresponding routine for that peripheral or software interrupt
source.
Reading the INTC_IACKR_PRC
n
acknowledges the INTC’s interrupt request and negates the interrupt
request to the processor. The interrupt request to the processor does not clear if a higher priority interrupt
request arrives. Even in this case, INTVEC does not update to the higher priority request until the lower
priority interrupt request is acknowledged by reading the INTC_IACKR_PRC
n
. The reading also pushes
the PRI value in the INTC current priority register (INTC_CPR_PRC
n
) onto the LIFO and updates PRI in
the INTC_CPR_PRC
n
with the priority of the interrupt request. The INTC_CPR_PRC
n
masks any
peripheral or software settable interrupt request at the same or lower priority of the current value of the
PRI field in INTC_CPR_PRC
n
from generating an interrupt request to the processor.
The interrupt exception handler must write to the end-of-interrupt register (INTC_EOIR_PRC
n
) to
complete the operation. Writing to the INTC_EOIR_PRC
n
ends the servicing of the interrupt request. The
INTC’s LIFO is popped into the INTC_CPR_PRC
n
’s PRI field by writing to the INTC_EOIR_PRC
n
, and
+
=
IVPR
0
19 20
31
Vector base
0x000
IVOR4
0
31
0x0000_0040
Software Vector Mode Interrupt Exception Handler Address
0
19 20
31
Vector base
0x040
31
16
15
0
IVPR
31
28
27
16
15
0
+ IVOR4
31
28
27
16
15
0
0x00
0x00
OFFSET
OFFSET
PREFIX
0x0000
PREFIX
= Interrupt exception
0x0000
handler address
Summary of Contents for PXN2020
Page 1: ...PXN20 Microcontroller Reference Manual Devices Supported PXN2020 PXN2120 PXN20RM Rev 1 06 2011...
Page 42: ...PXN20 Microcontroller Reference Manual Rev 1 lxiv Freescale Semiconductor...
Page 64: ...Introduction PXN20 Microcontroller Reference Manual Rev 1 1 22 Freescale Semiconductor...
Page 112: ...Signal Description PXN20 Microcontroller Reference Manual Rev 1 3 44 Freescale Semiconductor...
Page 118: ...Resets PXN20 Microcontroller Reference Manual Rev 1 4 6 Freescale Semiconductor...
Page 372: ...e200z6 Core Z6 PXN20 Microcontroller Reference Manual Rev 1 13 8 Freescale Semiconductor...
Page 412: ...e200z0 Core Z0 PXN20 Microcontroller Reference Manual Rev 1 14 14 Freescale Semiconductor...
Page 821: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 Freescale Semiconductor 27 49...
Page 822: ...Media Local Bus MLB PXN20 Microcontroller Reference Manual Rev 1 27 50 Freescale Semiconductor...
Page 1376: ...Memory Map PXN20 Microcontroller Reference Manual Rev 1 A 118 Freescale Semiconductor...