MC33910BAC / MC34910BAC
FUNCTIONAL DEVICE OPERATIONS
LOGIC COMMANDS AND REGISTERS
MOD2, MOD1 - Mode Control Bits
Any access to the MCR or voltage status register (VSR)
will clear the BATFAIL flag.
These write-only bits select the Operating mode and allow
to clear the watchdog in accordance with Table 38 Mode
Control Bits.
1 = POR Reset has occurred
0 = POR Reset has not occurred
Table 40. Mode Control Bits
Wake-up Control Register - WUCR
MOD2
MOD1
Description
This register is used to control the digital wake-up input.
Writing the wake-up control register (WUCR) will return the
wake-up status register (WUSR).
0
0
1
1
0
1
0
1
Normal Mode
Stop Mode
Sleep Mode
Table 42. Wake-up Control Register - $2
Normal Mode + watchdog Clear
C3
C2
C1
C0
Write
0
0
0
L1WE
Voltage Status Register - VSR
Returns the status of the several voltage monitors. This
register is also returned when writing to the MCR.
Reset
Value
1
1
1
1
Reset
Condition
Table 41. Voltage Status Register - $0/$1
POR, Reset mode or ext_reset
S3
S2
S1
S0
L1WE - Wake-up Input Enable
Read
VSOV
VSUV
VDDOT BATFAIL
This write-only bit enables/disables the L1 input. In Stop
and Sleep mode the L1WE bit activates the L1 input for wake-
up. If the L1 input is selected on the analog multiplexer, the
L1WE is masked to 0.
VSOV - VSUP Over-voltage
This read-only bit indicates an over-voltage condition on
the VS1 pin.
1 = Wake-up Input enabled.
0 = Wake-up Input disabled.
1 = Over-voltage condition.
0 = Normal condition.
Wake-up Status Register - WUSR
VSUV - VSUP Under-voltage
This register is used to monitor the digital wake-up inputs
and is also returned when writing to the wake-up control
register (WUCR).
This read-only bit indicates an under-voltage condition on
the VS1 pin.
1 = Under-voltage condition.
0 = Normal condition.
Table 43. Wake-up Status Register - $2/$3
S3
S2
S1
S0
VDDOT - Main Voltage Regulator Over-temperature
Warning
Read
-
-
-
L1
This read-only bit indicates that the main voltage regulator
temperature reached the Over-Temperature Prewarning
Threshold.
L1 - Wake-up input
This read-only bit indicates the status of the L1 input. If the
L1 input is not enabled then the wake-up status will return 0.
1 = Over-temperature prewarning
0 = Normal
After a wake-up form Stop or Sleep mode this bit also
allows to verify the L1 input has caused the wake-up, by first
reading the interrupt status register (ISR) and then reading
the wake-up status register (WUSR).
BATFAIL - Battery Fail Flag.
This read-only bit is set during power-up and indicates that
the 33910 had a power on reset (POR).
1 = L1 Wake-up.
0 = L1 Wake-up disabled or selected as analog input.
33910
Analog Integrated Circuit Device Data
Freescale Semiconductor
80
FREESCALE [ Freescale ]
