Analog Devices ADSP-BF506F Hardware Reference Manual page 747

The disable internal loop bit (
output to be routed back to the receive input.
The disable transmit output bit (
pin. When this bit is set, the
The disable receive input bit (
When set, the internal logic receives recessive bits or receives the internally
generated transmit value in the case of the internal loop enabled (
In either case, the value on the
The disable error counters bit (
receive error counters in the
holds its current contents and is not allowed to increment or dec-
CAN_CEC
rement the error counters. This mode does not conform to the CAN
specification.

Writes to the error counters should be in debug mode only. Write
access during reception may lead to undefined values. The maxi-
mum value which can be written into the error counters is 255.
Thus, the error counter value of 256 which forces the module into
the bus off state can not be written into the error counters.
Table 17-4 shows several common combinations of test mode bits.
Table 17-4. CAN Test Modes
MAA
MRB
X X
0 X
1 0
ADSP-BF50x Blackfin Processor Hardware Reference
) is used to internally enable the transmit
DIL
DTO
CANTX
DRI
CANRX
DEC
CAN_CEC
DIL DTO DRI
X X X
X X X
1 0 0
) is used to disable the
pin continuously drives recessive bits.
) is used to disable the
input pin is ignored.
) is used to disable the transmit and
register. When this bit is set, the
CDE Functional Description
0 Normal mode, not debug mode.
X No read back of transmit message.
1 Normal transmission on CAN bus
line.
Read back.
External acknowledge from external
device required.
CAN Module
output
CANTX
input.
CANRX
).
DIL=0
17-35