Datasheet

Resets, Interrupts, and System Configuration
MC9S08GT16A/GT8A Data Sheet, Rev. 1
78 Freescale Semiconductor
5.7.8 System Power Management Status and Control 2 Register (SPMSC2)
This register is used to report the status of the low voltage warning function, and to configure the stop mode
behavior of the MCU.
Figure 5-10. System Power Management Status and Control 2 Register (SPMSC2)
76543210
R
LVWF
0
LVDV LVWV
PPDF
0
PDC PPDC
W
LVWAC K PPDACK
Power-on
reset:
0
Note
(1)
1
LVWF will be set in the case when V
Supply
transitions below the trip point or after reset and V
Supply
is already below V
LVW
.
0000000
LVD reset: 0
Note
(1)
0UU0000
Any other
reset:
0
Note
(1)
0UU0000
= Unimplemented or Reserved U = Unaffected by reset
Table 5-11. SPMSC2 Field Descriptions
Field Description
7
LVWF
Low-Voltage Warning Flag — The LVWF bit indicates the low voltage warning status.
0 Low voltage warning not present.
1 Low voltage warning is present or was present.
6
LVWACK
Low-Voltage Warning Acknowledge — The LVWACK bit is the low-voltage warning acknowledge. Writing a 1
to LVWACK clears LVWF to 0 if a low voltage warning is not present.
5
LVDV
Low-Voltage Detect Voltage Select — The LVDV bit selects the LVD trip point voltage (V
LVD
).
0 Low trip point selected (V
LVD
= V
LVDL
).
1 High trip point selected (V
LVD
= V
LVDH
).
4
LVWV
Low-Voltage Warning Voltage Select — The LVWV bit selects the LVW trip point voltage (V
LVW
).
0 Low trip point selected (V
LVW
= V
LVWL
).
1 High trip point selected (V
LVW
= V
LVWH
).
3
PPDF
Partial Power Down Flag — The PPDF bit indicates that the MCU has exited the stop2 mode.
0 Not stop2 mode recovery.
1 Stop2 mode recovery.
2
PPDACK
Partial Power Down Acknowledge — Writing a 1 to PPDACK clears the PPDF bit.
1
PDC
Power Down Control — The write-once PDC bit controls entry into the power down (stop2 and stop1) modes.
0 Power down modes are disabled.
1 Power down modes are enabled.
0
PPDC
Partial Power Down Control — The write-once PPDC bit controls which power down mode, stop1 or stop2, is
selected.
0 Stop1, full power down, mode enabled if PDC set.
1 Stop2, partial power down, mode enabled if PDC set.