33912 Datasheet, PDF (36/47 Pages) Freescale Semiconductor, Inc – LIN System Basis Chip with DC Motor Pre-driver and Current

FUNCTIONAL DEVICE OPERATIONS
LOGIC COMMANDS AND REGISTERS
REGISTER DEFINITIONS
System Status Register - SYSSR
The System Status Register (SYSSR) is always
transferred with every SPI transmission and gives a quick
system status overview. It summarizes the status of the
Voltage Status Register (VSR), LIN Status Register (LINSR),
High Side Status Register (HSSR), and the Low Side Status
Register (LSSR).
Table 8. System Status Register
S7
S6
S5
S4
Read
VMS
LINS
HSS
LSS
VMS - Voltage Monitor Status
This read-only bit indicates that one or more bits in the
VSR are set.
1 = Voltage Monitor bit set
0 = None
BATFAIL
VDDOT
VSUV
VSOV
VMS
Figure 21. Voltage Monitor Status
LINS - LIN Status
This read-only bit indicates that one or more bits in the
LINSR are set.
1 = LIN Status bit set
0 = None
LINOC
LINOT
TXDOM
RXSHORT
LINS
Figure 22. LIN Status
HSS - High Side Switch Status
This read-only bit indicates that one or more bits in the
HSSR are set.
1 = High Side Status bit set
0 = None
HS1CL
HS1OP
HS2CL
HS2OP
HSS
Figure 23. High Side Status
LSS - Low Side Switch Status
This read-only bit indicates that one or more bits in the
LSSR are set.
1 = Low Side Status bit set
0 = None
LS1CL
LS1OP
LSS
LS2CL
LS2OP
Figure 24. Low Side Status
Mode Control Register - MCR
The Mode Control Register (MCR) allows switching
between the operation modes and to configure the 33912.
Writing the MCR will return the VSR.
Table 9. Mode Control Register - $0
C3
C2
C1
C0
Write
HVSE
LINPE
MOD2
MOD1
Reset
Value
1
1
-
-
Reset
Condition
POR
POR
-
-
HVSE - High-Voltage Shutdown Enable
This write-only bit enables/disables automatic shutdown of
the high side and the low side drivers during a high-voltage
VSOV condition.
1 = automatic shutdown enabled
0 = automatic shutdown disabled
LINPE - LIN pull-up enable.
This write-only bit enables/disables the 30kΩ LIN pull-up
resistor in STOP and SLEEP Modes. This bit also controls
the LIN bus wake-up threshold.
1 = LIN pull-up resistor enabled
0 = LIN pull-up resistor disabled
33912
36
Analog Integrated Circuit Device Data
Freescale Semiconductor