Development Support
MPC561/MPC563 Reference Manual, Rev. 1.2
23-28
Freescale Semiconductor
Not all exceptions are recognized when in debug mode. Breakpoints and watchpoints are not generated by
the hardware when in debug mode (regardless of the value of MSR[RI]). Upon entering debug mode
MSR[EE] is cleared by the hardware thus forcing the hardware to ignore external and decrementer
interrupts.
WARNING
Setting the MSR[EE] bit while in debug mode, (by the debug software), is
strictly forbidden. The reason for this restriction is that the external interrupt
event is a level signal, and since the CPU only reports exceptions while in
debug mode but do not treat them, the CPU does not clear the MSR[EE] bit
and, therefore, this event, if enabled, is recognized again every clock cycle.
When the ecr_or signal is asserted the development station should investigate the exception cause register
(ECR) in order to find out the event that caused the exception.
Since the values in SRR0 and SRR1 do not change if an exception is recognized while already in debug
mode, they only change once when entering debug mode, saving them when entering debug mode is not
necessary.
23.3.1.6
Exiting Debug Mode
The rfi instruction is used to exit from debug mode in order to return to the normal processor operation and
to negate the freeze indication. The development system may monitor the freeze status to make sure the
MPC561/MPC563 is out of debug mode. It is the responsibility of the software to read the exception cause
register (ECR) before performing the rfi. Failing to do so will force the CPU to immediately re-enter to
debug mode and to re-assert the freeze indication in case an asserted bit in the interrupt cause register
(ECR) has a corresponding enable bit set in the debug enable register (DER).
23.4
Development Port
The development port provides a full duplex serial interface for communications between the internal
development support logic including debug mode and an external development tool.
The relationship of the development support logic to the rest of the CPU chip is shown in
. The
development port support logic is shown as a separate block for clarity. It is implemented as part of the
SIU module.
23.4.1
Development Port Pins
The following development port pin functions are provided:
1. Development serial clock (DSCK)
2. Development serial data in (DSDI)
3. Development serial data out (DSDO)
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...