System Interface Unit (SIU)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
4-24 Freescale Semiconductor
4.3.1.6 SIU Interrupt Vector Register (SIVEC)
The SIU interrupt vector register (SIVEC), shown in Figure4- 18, contains an 8-bit code representing the
unmasked interrupt source of the highest priority level.
The SIVEC can be read as either a byte, half word, or a word. When read as a byte, a branch table can be
used in which each entry contains one instruction (branch). When read as a half word, each entry can
contain a full routine of up to 256 instructions. The interrupt code is defined such that its two lsbs are
zeroes, allowing indexing into the table, as shown in Figure 4-19.
0 5 6 7 8 9 10 11 12 13 14 15
Field Interrupt Code 0000000000
Reset 0000_0000_0000_0000
R/W R
Addr 0x0x10C04
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Field0000000000000000
Reset 0000_0000_0000_0000
R/W R
Addr 0x10C06
Figure 4-18. SIU Interrupt Vector Register (SIVEC)