NXP Semiconductors MPC5606S - Page 1081

Reset Generation Module (MC_RGM)
MPC5606S Microcontroller Reference Manual, Rev. 7
Freescale Semiconductor 1079
NOTE
The F_POR flag is automatically cleared on a 1.2V low-voltage detected
(power domain #0 or #1) or a 2.7V low-voltage detected (VREG). This
means that if the startup sequence is not monotonic (i.e the voltage rises and
then drops enough to trigger a low-voltage detection), the F_POR flag may
not be set but instead the <register>F_LVD12_PD0,
<register>F_LVD12_PD1, or <register>F_LVD27_VREG flag is set on
exiting the reset sequence. Therefore, if the F_POR,
<register>F_LVD12_PD0, <register>F_LVD12_PD1, or
<register>F_LVD27_VREG flags are set on reset exit, software should
interpret the reset cause as power-on.
NOTE
In contrast to all other reset sources, the 1.2V low-voltage detected (power
domain #0) event is captured on its deassertion. Therefore, the status bit
F_LVD12_PD0 is also asserted on the reset’s deassertion. In case an
alternate event is selected, the Safe mode or interrupt request are similarly
asserted on the reset’s deassertion.
Table 31-4. Destructive Event Status Register (RGM_DES) field descriptions
Field Description
F_POR Flag for Power-On reset
0 No power-on event has occurred since the last clear (due to either a software clear or a low-voltage detection)
1 A power-on event has occurred
F_LVD27 Flag for 2.7V low-voltage detected
0 No 2.7V low-voltage detected event has occurred since either the last clear or the last power-on reset
assertion
1 A 2.7V low-voltage detected event has occurred
F_SWT Flag for software watchdog timer
0 No software watchdog timer event has occurred since either the last clear or the last power-on reset assertion
1 A software watchdog timer event has occurred
F_LVD12_P
D1
Flag for 1.2V low-voltage detected (power domain #1)
0 No 1.2V low-voltage detected (power domain #1) event has occurred since either the last clear or the last
power-on reset assertion
1 A 1.2V low-voltage detected (power domain #1) event has occurred
F_LVD12_P
D0
Flag for 1.2V low-voltage detected (power domain #0)
0 No 1.2V low-voltage detected (power domain #0) event has occurred since either the last clear or the last
power-on reset assertion
1 A 1.2V low-voltage detected (power domain #0) event has occurred