Central Processing Unit
MPC561/MPC563 Reference Manual, Rev. 1.2
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Freescale Semiconductor
operating system should set the RI bit in the MSR at the end of each exception handler’s prologue (after
saving the program state) and clear the bit at the start of each exception handler’s epilogue (before
restoring the program state). Then, if an unordered exception occurs during the servicing of an exception
handler, the RI bit in SRR1 will contain the correct value.
3.11.4
Precise Exceptions
In the RCPU, all synchronous (instruction-caused) exceptions are precise. When a precise exception
occurs, the processor backs the machine up to the instruction causing the exception. This ensures that the
machine is in its correct architecturally-defined state. The following conditions exist at the point a precise
exception occurs:
1. Architecturally, no instruction following the faulting instruction in the code stream has begun
execution.
2. All instructions preceding the faulting instruction appear to have completed with respect to the
executing processor.
3. SRR0 addresses either the instruction causing the exception or the immediately following
instruction. Which instruction is addressed can be determined from the exception type and the
status bits.
4. Depending on the type of exception, the instruction causing the exception may not have begun
execution, may have partially completed, or may have completed execution.
3.11.5
Exception Vector Table
The setting of the exception prefix (IP) bit in the MSR determines how exceptions are vectored. If the bit
is cleared, the exception vector table begins at the physical address 0x0000 0000; if IP is set, the exception
vector table begins at the physical address 0xFFF0 0000.
shows the exception vector offset of
the first instruction of the exception handler routine for each exception type.
NOTE
In the MPC561/MPC563, the exception table can additionally be relocated
by the BBC module to internal memory and reduce the total size required by
the exception table (see
Section 4.3, “Exception Table Relocation (ETR)
Table 3-19. Exception Vector Offset Table
Vector Offset
(hex)
Exception Type
Section
00000
Reserved
—
00100
System reset, NMI interrupt
Section 3.15.4.1, “System Reset Exception and NMI (0x0100)
”
00200
Machine Check
Section 3.15.4.2, “Machine Check Exception (0x0200)
00300
Data Storage
Section 3.15.4.3, “Data Storage Exception (0x0300)
”
00400
Reserved
Instruction Storage
1
00500
External Interrupt
Summary of Contents for MPC561
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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...
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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...