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In this mode, the sent data are directly transmitted to the input end for receiving,
the data are not received from the bus, and all data can be sent to the bus.
Figure 108 CAN Works in Loopback Mode
TX
RX
MCU
CANTX
CANRX
Loopback silent mode
Set the LBKMEN and SILMEN bits of the configuration register CAN_BITTIM to
1 and select the loopback silent mode.
In this mode, the sent data are directly transmitted to the input end for receiving,
and the data are not received from the bus; only recessive bit (logic 1) can be
sent to the bus, while the dominant bit (logic 0) cannot be sent.
Figure 109 CAN Works in Silent Loopback Mode
TX
RX
MCU
=1
CANTX
CANRX
Normal mode
In this mode, data can be sent to the bus and be received from the bus.