Chapter 7 Mode Entry Module (MC_ME)
MPC5602P Microcontroller Reference Manual, Rev. 4
174
Freescale Semiconductor
Whenever an invalid mode request is detected, the interrupt pending bit I_IMODE of the ME_IS register
is set, and an interrupt request is generated if the mask bit M_IMODE of the ME_IM register is ‘1’.
7.4.5.3
SAFE Mode Transition Interrupt
Whenever the system enters the SAFE mode as a result of a SAFE mode request from the MC_RGM due
to a hardware failure, the interrupt pending bit I_SAFE of the ME_IS register is set, and an interrupt is
generated if the mask bit M_SAFE of ME_IM register is ‘1’.
The SAFE mode interrupt pending bit can be cleared only when the SAFE mode request is deasserted by
the MC_RGM (see the MC_RGM chapter for details on how to clear a SAFE mode request). If the system
is already in SAFE mode, any new SAFE mode request by the MC_RGM also sets the interrupt pending
bit I_SAFE. However, the SAFE mode interrupt pending bit is not set when the SAFE mode is entered by
a software request (i.e., programming of ME_MCTL register).
7.4.5.4
Mode Transition Complete Interrupt
Whenever the system fully completes a mode transition (i.e., the S_MTRANS bit of ME_GS register
transits from ‘1’ to ‘0’), the interrupt pending bit I_MTC of the ME_IS register is set, and an interrupt
request is generated if the mask bit M_MTC of the ME_IM register is ‘1’. The interrupt bit I_MTC is not
set when entering low-power modes HALT0 and STOP0 in order to avoid the same event requesting the
immediate exit of these low-power modes.
7.4.6
Peripheral Clock Gating
During all device modes, each peripheral can be associated with a particular clock gating policy
determined by two groups of peripheral configuration registers.
The run peripheral configuration registers ME_RUN_PC0…7 are chosen only during the software running
modes DRUN, TEST, SAFE, and RUN0…3. All configurations are programmable by software according
to the needs of the application. Each configuration register contains a mode bit which determines whether
or not a peripheral clock is to be gated. Run configuration selection for each peripheral is done by the
RUN_CFG bit field of the ME_PCTL0…143 registers.
The low-power peripheral configuration registers ME_LP_PC0…7 are chosen only during the low-power
modes HALT0 and STOP0. All configurations are programmable by software according to the needs of
the application. Each configuration register contains a mode bit which determines whether or not a
peripheral clock is to be gated. Low-power configuration selection for each peripheral is done by the
LP_CFG bit field of the ME_PCTL0…143 registers.
Any modifications to the ME_RUN_PC0…7, ME_LP_PC0…7, and ME_PCTL0…143 registers do not
affect the clock gating behavior until a new mode transition request is generated.
Whenever the processor enters a debug session during any mode, the following occurs for each peripheral:
•
The clock is gated if the DBG_F bit of the associated ME_PCTL0…143 register is set. Otherwise,
the peripheral clock gating status depends on the RUN_CFG and LP_CFG bits. Any further
modifications of the ME_RUN_PC0…7, ME_LP_PC0…7, and ME_PCTL0…143 registers
during a debug session will take affect immediately without requiring any new mode request.