ST SPC560P34 - Figure 232. Linflex Operating Modes

RM0046 LIN Controller (LINFlex)
Doc ID 16912 Rev 5 489/936
21.5 Operating modes
LINFlex has three main operating modes: Initialization, Normal and Sleep. After a hardware
reset, LINFlex is in Sleep mode to reduce power consumption. The software instructs
LINFlex to enter Initialization mode or Sleep mode by setting the INIT bit or SLEEP bit in the
LINCR1.
Figure 232. LINFlex operating modes
21.5.1 Initialization mode
The software can be initialized while the hardware is in Initialization mode. To enter this
mode the software sets the INIT bit in the LINCR1.
To exit Initialization mode, the software clears the INIT bit.
While in Initialization mode, all message transfers to and from the LIN bus are stopped and
the status of the LIN bus output LINTX is recessive (high).
Entering Initialization mode does not change any of the configuration registers.
To initialize the LINFlex controller, the software selects the mode (LIN Master, LIN Slave or
UART), sets up the baud rate register and, if LIN Slave mode with filter activation is
selected, initializes the identifier list.
21.5.2 Normal mode
Once initilization is complete, software clears the INIT bit in the LINCR1 to put the hardware
into Normal mode.
21.5.3 Low power mode (Sleep)
To reduce power consumption, LINFlex has a low power mode called Sleep mode. To enter
Sleep mode, software sets the SLEEP bit in the LINCR1. In this mode, the LINFlex clock is
stopped. Consequently, the LINFlex will not update the status bits but software can still
access the LINFlex registers.
LINFlex can be awakened (exit Sleep mode) either by software clearing the SLEEP bit or on
detection of LIN bus activity if automatic wake-up mode is enabled (AWUM bit is set).
SLEEP
INITIALIZATION
NORMAL
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RESET
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SL
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