NXP Semiconductors MPC5606S - Target Mode Request

Mode Entry Module (MC_ME)
MPC5606S Microcontroller Reference Manual, Rev. 7
940 Freescale Semiconductor
to be executed based on the mode control information, and some steps may not be valid according to the
mode definition itself.
25.4.3.1 Target mode request
The target mode is requested by accessing the ME_MCTL register with the required keys. This mode
transition request by software must be a valid request satisfying a set of pre-defined rules to initiate the
process. If the request fails to satisfy these rules, it is ignored, and the TARGET_MODE bit field is not
updated. An optional interrupt can be generated for invalid mode requests. Refer to Section 25.4.5, Mode
transition interrupts, for details.
In the case of mode transitions occurring because of hardware events such as a reset, a Safe mode request,
or interrupt requests and wakeup events to exit from low-power modes, the TARGET_MODE bit field of
the ME_MCTL register is automatically updated with the appropriate target mode. The mode change
process start is indicated by the setting of the mode transition status bit S_MTRANS of the ME_GS
register.
A Reset mode requested via the ME_MCTL register is passed to the MC_RGM, which generates a global
system reset and initiates the reset sequence. The Reset mode request has the highest priority, and the
MC_ME is kept in the Reset mode during the entire reset sequence.
The Safe mode request has the next highest priority after reset which can be generated by software via the
ME_MCTL register from all software running modes including DRUN, Run0…3, and Test or by the
MC_RGM after the detection of system hardware failures, which may occur in any mode.
25.4.3.2 Target mode configuration loading
On completion of the Target mode request, the target mode configuration from the
ME_<target mode>_MC register is loaded to start the resources (voltage sources, clock sources, flashes,
pads, etc.) control process.
An overview of resource control possibilities for each mode is shown in Table 25-16. A ‘’ indicates that
a given resource is configurable for a given mode.
Table 25-16. MC_ME resource control overview
Resource
Mode
Reset Test Safe DRUN Run0…3 Halt Stop Standby
FIRC    
on always on on on on always on always on on
FXOSC     
off off off off off off off off by
default, but
also
writable
FMPLL0    
off off off off off off off off