MC68F375
CAN 2.0B CONTROLLER MODULE
MOTOROLA
REFERENCE MANUAL
Rev. 25 June 03
7-32
8
RXWARN
Receiver error status flag. The RXWARN status flag reflects the status of the TouCAN
receive error counter.
0 = Receive error counter
< 96.
1 = Receive error counter
≥ 96.
7IDLE
Idle status. The IDLE bit indicates when there is activity on the CAN bus.
0 = The CAN bus is not idle.
1 = The CAN bus is idle.
6TX/RX
Transmit/receive status. The TX/
RX bit indicates when the TouCAN module is transmitting
or receiving a message. TX/
RX has no meaning when IDLE = 1.
0 = The TouCAN is receiving a message if IDLE = 0.
1 = The TouCAN is transmitting a message if IDLE = 0.
5:4
FCS
Fault confinement state. The FCS[1:0] field describes the state of the TouCAN. Refer to
If the SOFTRST bit in CANMCR is asserted while the TouCAN is in the bus off state, the
error and status register is reset, including FCS[1:0]. However, as soon as the TouCAN exits
more information on entry into and exit from the various fault confinement states.
3—
Reserved
2
BOFFINT
Bus off interrupt. The BOFFINT bit is used to request an interrupt when the TouCAN enters
the bus off state.
0 = No bus off interrupt requested.
1 = When the TouCAN state changes to bus off, this bit is set, and if the BOFFMSK bit in
CANCTRL0 is set, an interrupt request is generated. This interrupt is not requested after
reset.
1
ERRINT
Error Interrupt. The ERRINT bit is used to request an interrupt when the TouCAN detects a
transmit or receive error.
0 = No error interrupt request.
1 = If an event which causes one of the error bits in the error and status register to be set
occurs, the error interrupt bit is set. If the ERRMSK bit in CANCTRL0 is set, an interrupt
request is generated.
To clear this bit, first read it as a one, then write as a zero. Writing a one has no effect.
0
WAKEINT
Wake interrupt. The WAKEINT bit indicates that bus activity has been detected while the
TouCAN module is in low-power stop mode.
0 = No wake interrupt requested.
1 = When the TouCAN is in low-power stop mode and a recessive to dominant transition is
detected on the CAN bus, this bit is set. If the WAKEMSK bit is set in CANMCR, an in-
terrupt request is generated.
Table 7-22 Transmit Bit Error Status
BITERR[1:0]
Bit Error Status
00
No transmit bit error
01
At least one bit sent as dominant was received as recessive
10
At least one bit sent as recessive was received as dominant
11
Not used
Table 7-21 ESTAT Bit Settings (Continued)
Bit(s)
Name
Description
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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