
System Integration Module
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System Integration Module
MOTOROLA
MCF5206 USERS MANUAL Rev 1.0
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is reserved and is set to zero, and cannot be changed. The value of the software watchdog
interrupt vector register is always used as the interrupt vector number for a SWT interrupt.
You can program the timer modules interrupt levels and priorities using the interrupt level
(IL2 - IL0) and interrupt priority (IP1, IP0) bits in the appropriate interrupt control registers
(ICR9, ICR10). The timer peripherals cannot provide interrupt vectors. Thus, autovector bits
in ICR9 and ICR10 are set to 1. You cannot change this value. This generates autovectors
in response to all timer interrupts.
You can also program the MBUS module interrupt level and priority using the interrupt level
(IL2 - IL0) and interrupt priority (IP1, IP0) bits in the MBUS interrupt control register, ICR11.
You cannot program the MBUS module to provide an interrupt vector. Thus, the autovector
bit in ICR11 is set to 1. You cannot change this value. This generates an autovector in
response to an MBUS interrupt.
You can program the UART module interrupt levels and priorities using the interrupt level
(IL2 - IL0) and interrupt priority (IP1, IP0) bits in the appropriate interrupt control registers
(ICR12, ICR13). In addition, you can program the autovector bits in ICR12 and ICR13. If the
autovector bit is set to 0, you must program the interrupt vector register in each UART
module to the preferred vector number.
The interrupt controller monitors and masks individual interrupt inputs and outputs the
highest priority unmasked pending interrupt to the ColdFire core. Each interrupt input has a
mask bit in the interrupt mask register (IMR) and a pending bit in the interrupt pending
register (IPR). The pending bits for all internal interrupts in the interrupt pending register are
set the CLK cycle after the interrupt is asserted whether or not the interrupt is masked. If you
program the external interrupt inputs as individual interrupt inputs, the pending bits in the
interrupt pending register are set to the CLK cycle after the interrupt is asserted and
internally synchronized.
If you program the external interrupt inputs to indicate interrupt priority levels, the interrupt
pending bits are set and cleared as follows:
1. EINT[7:1] is set the CLK cycle after the interrupt level has been internally synchronized
and indicated the same valid level for two consecutive CLK cycles.
2. The interrupt pending bits EINT[7:1] remains set if the external interrupt level remains
the same or increases in priority.
3. The interrupt pending bits EINT[7:1] is cleared if the external interrupt level decreases
in priority or if an interrupt acknowledge cycle is completed for an external interrupt that
is pending but is not the current level being driven onto the external interrupt priority
level signals (IPLx/IRQx).
For example, if you program the external interrupts to indicate interrupt priority levels and
assert to indicate a level 3 interrupt, and then assert to indicate a level 6 interrupt, both
EINT3 and EINT6 bits in the interrupt pending register is set. This indicates that both an
external level 6 and an external level 3 interrupt is pending.If the level 3 interrupt is now
acknowledged (by completing an interrupt acknowledge cycle for a level 3 interrupt), EINT3
is cleared and only EINT6 remains set. If the interrupt priority level is now changed to
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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