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Interrupt Controller Modules
Freescale Semiconductor
14-15
14.2.10 Software and Level 1 – 7 IACK Registers (SWIACKn, L1IACKn –
L7IACKn)
The eight IACK registers (per interrupt controller) can be explicitly addressed via the CPU, or implicitly
addressed via a processor-generated interrupt acknowledge cycle during exception processing. In either
case, the interrupt controller’s actions are very similar.
First, consider an IACK cycle to a specific level: a level-
n
IACK. When this type of IACK arrives in the
interrupt controller, the controller examines all the currently-active level
n
interrupt requests, determines
the highest priority within the level, and then responds with the unique vector number corresponding to
that specific interrupt source. The vector number is supplied as the data for the byte-sized IACK read cycle.
In addition to providing the vector number, the interrupt controller also loads the level into the CLMASK
register, where it may be retrieved later.
This interrupt controller design also supports the concept of a software IACK. A software IACK allows
an interrupt service routine to determine if there are other pending interrupts so that the overhead
associated with interrupt exception processing (including machine state save/restore functions) can be
minimized. In general, the software IACK is performed near the end of an interrupt service routine, and if
there are additional active interrupt sources, the current interrupt service routine (ISR) passes control to
the appropriate service routine, but without taking another interrupt exception.
When the interrupt controller receives a software IACK read, it returns the vector number associated with
the highest unmasked interrupt source for that interrupt controller. If there are no active sources, the
interrupt controller returns an all-zero vector as the operand for the SWIACK register. A read from the
L
n
IACK registers when there are no active requests returns a value of 24 (0x18), signaling a spurious
interrupt.
In addition to the software IACK registers in each interrupt controller, there are global software IACK
registers. A read from the global SWIACK (GSWIACK) returns the vector number for the highest level
and priority unmasked interrupt source from all interrupt controllers. A read from one of the global
L
n
IACK (GL
n
IACK) registers returns the vector for the highest priority unmasked interrupt within a level
for all interrupt controllers.
51
LCDC
LCD_ISR
LCD controller interrupt
Read the LCD_ISR register.
52
RTC
RTC_ISR
Real time clock interrupt
Write one to corresponding bit in RTC_ISR.
53
CCM
UHCSR or UOCSR
USB status Interrupt
Read UHCSR or read UOCSR.
54–63
Not Used
Table 14-16. Interrupt Source Assignment for INTC1 (continued)
Source Module
Flag
Source
Description
Flag Clearing Mechanism
MCF5329 Reference Manual, Rev 3
Summary of Contents for MCF5329
Page 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...