Burst Buffer Controller 2 Module
MPC561/MPC563 Reference Manual, Rev. 1.2
4-8
Freescale Semiconductor
Figure 4-2. Exception Table Entries Mapping
4.3.1
ETR Operation
The exception vectors generated by the RCPU are 0x100 bytes apart from each other, starting at address
0x0000 0100 or 0xFFF0 0100, depending on the value of MSR[IP] bit in the RCPU.
If the exception table relocation is disabled by the ETRE bit in the BBCMCR register, the BBC transfers
the exception fetch address to the U-bus of the MPC561/MPC563 with no interference. In this case, normal
PowerPC ISA exception addressing is implemented.
If the exception table relocation is enabled, the BBC translates the exception vector into the exception
relocation address as shown in
. At that location, a branch instruction with absolute addressing
(ba) must be placed. Each ba instruction branches to the required exception routine. These branch
instructions should be successive in that region of memory. That way, a table of branch instructions is
implemented. Executing the branch instruction causes the core to branch twice until it gets to the exception
routine.
Each exception relocation table entry occupies two words to support decompression on mode, where a
branch instruction can be more than 32 bits long. The branch table can be located in four locations in the
internal memory, the location is defined by BBCMCR[OERC] as shown in
100
200
300
400
500
600
700
1F00
Exce
p
ti
o
n
T
a
b
le
Exception Pointer by Core
Internal Memory Structure
branch to...
branch to...
branch to...
branch to...
branch to...
branch to...
branch to...
branch to...
branch to...
branch to...
branch to...
branch to...
Free Memory Space
0
branch to...
branch to...
1FFC
1FFC
0
8
10
Decompression
ON
N
Y
B8
.
.
.
.
.
.
.
.
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...