SH7052 Datasheet, PDF (559/919 Pages) Renesas Technology Corp – SuperHTM RISC engine

15.3 Operation
15.3.1 Hardware Reset and Software Reset
There are two ways of resetting the HCAN: Hardware reset, software reset
Hardware Reset (power-on reset or hardware/software standby): The MCR reset request bit
(MCR0) in MCR and the reset state bit (GSR3) in GSR within the HCAN are automatically set
and initialization is performed. At the same time, all internal registers are initialized. However
mailbox (RAM) contents are not initialized. A flowchart of this reset is shown in figure 15.5.
Software Reset: In normal operation, HCAN is initialized by setting the MCR reset request bit
(MCR0) in MCR. With this kind of reset, if the CAN controller is performing a communication
operation (transmission or reception), the initialization state is not entered until the message has
been completed. During initialization, the reset state bit (GSR3) in GSR is set. In this kind of
initialization, the error counters (TEC and REC) are initialized but other registers and RAM are
not. A flowchart of this reset is shown in figure 15.6.
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