
252
7682C–AUTO–04/08
AT90CAN32/64/128
– 0 - standby mode: the on-going communication is normally terminated and the CAN
channel is frozen (the CONMOB bits of every MOb do not change). The transmitter
constantly provides a recessive level. In this mode, the receiver is not enabled but all the
registers and mailbox remain accessible from CPU.
– 1 - enable mode: the CAN channel enters in enable mode once 11 recessive bits has
Bit 0 – SWRES: Software Reset Request
This auto resettable bit only resets the CAN controller.
– 0 - no reset
– 1 - reset: this reset is “ORed” with the hardware reset.
19.10.2
CAN General Status Register - CANGSTA
Bit 7 – Reserved Bit
This bit is reserved for future use.
Bit 6 – OVFG: Overload Frame Flag
This flag does not generate an interrupt.
– 0 - no overload frame.
– 1 - overload frame: set by hardware as long as the produced overload frame is sent.
Bit 5 – Reserved Bit
This bit is reserved for future use.
Bit 4 – TXBSY: Transmitter Busy
This flag does not generate an interrupt.
– 0 - transmitter not busy.
– 1 - transmitter busy: set by hardware as long as a frame (data, remote, overload or
error frame) or an ACK field is sent. Also set when an inter frame space is sent.
Bit 3 – RXBSY: Receiver Busy
This flag does not generate an interrupt.
– 0 - receiver not busy
– 1 - receiver busy: set by hardware as long as a frame is received or monitored.
Bit 2 – ENFG: Enable Flag
This flag does not generate an interrupt.
– 0 - CAN controller disable: because an enable/standby command is not immediately
effective, this status gives the true state of the chosen mode.
– 1 - CAN controller enable.
Bit
7
6
5
4
3
2
1
0
-
OVFG
-
TXBSY
RXBSY
ENFG
BOFF
ERRP
CANGSTA
Read/Write
-
R
-
R
Initial Value
-
0
-
0