NEC V850ES/F 3-L Series User Manual page 620

32-bit single-chip microcontroller

Table of Contents

Releasing CAN sleep mode

The CAN sleep mode is released by the following events:

• When the CPU writes 00

• A falling edge at the CAN reception pin (CRXDn) (i.e. the CAN bus level

shifts from recessive to dominant)

Even if the falling edge belongs to the SOF of a receive message, this

message will not be received and stored. If the CPU has turned off the clock

supply to the CAN module while the CAN module was in sleep mode, even

subsequently the CAN sleep mode will not be released and PSMODE [1:0] will

unless the clock to the CAN module is supplied again. In addition

to this, the receive message will not be received after that.

After releasing the sleep mode, the CAN module returns to the operation mode

from which the CAN sleep mode was requested and the PSMODE[1:0] bits of

the CnCTRL register must be reset by software to 00

is released by a change in the CAN bus state, the CINTS5 bit of the CnINTS

module is released from the CAN sleep mode, it participates in the CAN bus

again by automatically detecting 11 consecutive recessive-level bits on the

CAN bus. The user application has to wait until MBON = 1, before accessing

message buffers again.

When a request for transition to the initialization mode is made while the CAN

module is in the CAN sleep mode, that request is ignored; the CAN module

has to be released from sleep mode by software first before entering the

initialization mode.

Be aware that the release of CAN sleep mode by CAN bus event, and thus

the wake up interrupt may happen at any time, even right after requesting

sleep mode, if a CAN bus event occurs.

Always reset the PSMODE[1:0] bits to 00

mode, before accessing any other registers of the CAN module.

Always clear the interrupt flag CINTS5, when waking up from CAN sleep

User's Manual U18743EE1V2UM00

to the PSMODE[1:0] bits of the CnCTRL register

, when waking up from CAN sleep

CAN Controller (CAN)

. If the CAN sleep mode