XC161 Datasheet, PDF (284/419 Pages) Infineon Technologies AG – 16-Bit Single-Chip Microcontroller with C166SV2 Core Volume 2 (of 2): Peripheral Units

XC161 Derivatives
Peripheral Units (Vol. 2 of 2)
TwinCAN Module
21.1.8 Loop-Back Mode
The TwinCAN module’s loop-back mode provides the means to internally test the
TwinCAN module and CAN driver software. CAN driver software can be developed and
tested without being connected to a CAN bus system.
In loop-back mode, the transmit pins deliver recessive signals to the transceiver. The
transmit signals are combined together and are connected to the internal receive signals,
as shown in Figure 21-25. The receive input pins are not taken into account in loop-back
mode.
RxDCA
RxDCB
MUX
0
1
MUX
0
1
TwinCAN
Kernel
&
MUX
0
11
TxDCA
MUX
0
11
TxDCB
LBM
MCA05495
Figure 21-25 Loop-back Mode
Loop-back mode is controlled by bits LBM in the bit timing registers of Node A and
Node B according to Table 21-5.
Table 21-5 Loop-Back Mode
ABTR.LBM BBTR.LBM Description
0
0
Loop-back mode is disabled.
0
1
Loop-back mode is disabled.
1
0
Loop-back mode is disabled.
1
1
Loop-back mode is enabled.
User’s Manual
TwinCAN_X1, V2.1
21-44
V2.2, 2004-01