Chapter 7 Mode Entry Module (MC_ME)
MPC5602P Microcontroller Reference Manual, Rev. 4
142
Freescale Semiconductor
7.3.2.2
Mode Control Register (ME_MCTL)
This register is used to trigger software-controlled mode changes. Depending on the modes as enabled by
ME_ME register bits, configurations corresponding to unavailable modes are reserved and access to
ME_<mode>_MC registers must respect this for successful mode requests.
NOTE
Byte and half-word write accesses are not allowed for this register as a
predefined key is required to change its value.
S_16
MHz_IRC
16 MHz internal RC oscillator status
0 16 MHz internal RC oscillator is not stable
1 16 MHz internal RC oscillator is providing a stable clock
S_SYSCLK
System clock switch status
— These bits specify the system clock currently used by the system.
0000 16 MHz int. RC osc.
0001 reserved
0010 4 MHz crystal osc.
0011 reserved
0100 system PLL
0101 reserved
0110 reserved
0111 reserved
1000 reserved
1001 reserved
1010 reserved
1011 reserved
1100 reserved
1101 reserved
1110 reserved
1111 system clock is disabled
Address
Access: User read, Supervisor read/write, Test read/write
R
TARGET_MODE
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
R
1
0
1
0
0
1
0
1
0
0
0
0
1
1
1
1
W
KEY
Reset
1
0
1
0
0
1
0
1
0
0
0
0
1
1
1
1
Figure 7-3. Mode Control Register (ME_MCTL)
Table 7-4. Global Status Register (ME_GS) Field Descriptions (continued)
Field
Description