PXS20RM Datasheet, PDF (1244/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

Reset Generation Module (MC_RGM)
Table 41-4. Destructive Event Status Register (RGM_DES) Field Descriptions (continued)
Field
Description
F_HVD12
F_LVD12
Flag for 1.2 V high-voltage detected
0 No 1.2 V high-voltage detected event has occurred since either the last clear or the last power-on
reset assertion
1 A 1.2 V high-voltage detected event has occurred
Flag for 1.2 V low-voltage detected
0 No 1.2 V low-voltage detected event has occurred since either the last clear or the last power-on
reset assertion
1 A 1.2 V low-voltage detected event has occurred
NOTE
The F_POR flag is automatically cleared on a 1.2 V low-voltage detected
or a 2.7 V low-voltage detected. This means that if the power-up 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
F_LVD12 or F_LVD27_VREG flag is set on exiting the reset sequence.
Therefore, if the F_POR, F_LVD12 or F_LVD27_VREG flags are set on
reset exit, software should interpret the reset cause as power-on.
41.3.1.3 Functional Event Reset Disable Register (RGM_FERD)
Address 0xC3FE_4004
Access: User read, Supervisor read/write, Test read/write
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
W
Reset^* 0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
* _{This register is reset if and only if one of thefollowing occurs:}
• Power up
• 1.2 V low-voltage detection (i.e. when the core voltage drops below the point at which the flip-flops can reliably retain
their value)
Figure 41-5. Functional Event Reset Disable Register (RGM_FERD)
This register provides dedicated bits to disable functional reset sources.When a functional reset source is
disabled, the associated functional event will trigger either a SAFE mode request or an interrupt request
(see Section 41.3.1.5, Functional Event Alternate Request Register (RGM_FEAR)). It can be accessed in
read/write in either supervisor mode or test mode. It can be accessed in read only in user mode. Each byte
can be written only once after power-on reset. Some fields are read-only, with a POR value of 1 or 0, and
the corresponding behavior cannot be changed.
41-12
PXS20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor