
Interrupt Controller Modules
14-20
Freescale Semiconductor
appropriate vector number. As the interrupt acknowledge read performs, the vector number returns to the
core. The contents of the CLMASK register load into the SLMASK register, and the CLMASK register
updates to the level of the acknowledge interrupt. Additionally, the processor raises the interrupt mask in
the status register (SR[I]) to match the level of the acknowledged request. At the end of the core’s
exception processing, control passes to the interrupt service routine (ISR), shown as the beginning of
segment C.
During C, the initial portion of the ISR executes. Near the end of this segment, the ISR accesses the
peripheral to negate the interrupt request source. At the conclusion of segment C, the SR[I] field can be
lowered to re-enable interrupts with a priority greater than the original request.
The bulk of the interrupt service routine executes in segment D, with interrupts enabled. Near the end of
the service routine, the SR[I] field is again raised to the original acknowledged level, preparing to perform
the context switch.
At the end of segment E, the original value in the saved level mask (SLMASK) is restored in the current
level mask (CLMASK). Optionally, the service routine can directly load the CLMASK register with any
value with pending interrupt requests of certain levels need to be examined.
In segment F, the interrupt service routine completes execution. During this period of time, it is possible
to access the interrupt controller with a software IACK to see if there are any pending properly-enabled
requests. Checking for any pending interrupt requests at this time provides ability to initiate processing of
another interrupt without the need to return from the original and incur the overhead of another interrupt
exception.
At the conclusion of segment G, the processor core returns to the original interrupted task or a different
task ready to execute.
Obviously, there are many variations to the managing of the SR[I] and the CLMASK values to create a
flexible, responsive system for managing interrupt requests within the device.
MCF5329 Reference Manual, Rev 3
Содержание MCF5329
Страница 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 126: ...Enhanced Multiply Accumulate Unit EMAC 4 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 564: ...Liquid Crystal Display Controller LCDC 22 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 692: ...Programmable Interrupt Timers PIT0 PIT3 28 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 720: ...Queued Serial Peripheral Interface QSPI 30 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 790: ...Message Digest Hardware Accelerator MDHA 33 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 902: ...Register Memory Map Quick Reference A 26 Freescale Semiconductor MCF5329 Reference Manual Rev 3...