System Interface Unit (SIU)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
4-16 Freescale Semiconductor
Note that the interrupt vector table differs from the interrupt priority table in only two ways:
FCC, SCC, and MCC vectors are fixed; they are not affected by the SCC group mode, spread mode,
or the relative priority order of the FCCs, SCCs, and MCC.
An error vector exists as the last entry in Ta ble 4- 3. The error vector is issued when no interrupt is
requesting service.
4.2.4.1 Port C External Interrupts
There are 16 external interrupts, coming from the parallel I/O port C pins, PC[0–15]. When ones of these
pins is configured as an input, a change according to the SIU external interrupt control register (SIEXR)
causes an interrupt request signal to be sent to the interrupt controller. PC[0–15] lines can be programmed
to assert an interrupt request upon any change. Each port C line asserts a unique interrupt request to the
interrupt pending register and has a different internal interrupt priority level within the interrupt controller.
44 TC Layer30b10_1100
45–47 Reserved 0b10_11xx
48 PC15 0b11_0000
49 PC14 0b11_0001
50 PC13 0b11_0010
51 PC12 0b11_0011
52 PC11 0b11_0100
53 PC10 0b11_0101
54 PC9 0b11_0110
55 PC8 0b11_0111
56 PC7 0b11_1000
57 PC6 0b11_1001
58 PC5 0b11_1010
59 PC4 0b11_1011
60 PC3 0b11_1100
61 PC2 0b11_1101
62 PC1 0b11_1110
63 PC0 0b11_1111
1On MPC8250, MPC8265, and MPC8266 only. Reserved on all other devices.
2Reserved on MPC8250 and MPC8255.
3On MPC8264 and MPC8266 only. Reserved on all other devices.
Table4- 3. Encoding the Interrupt Vector (continued)
Interrupt Number Interrupt Source Description Interrupt Vector