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MPC5668EVB Users Manual Rev 0.1 May 2009
MPC5668EVBUM/D Page 15 of 29
The CAN section is located
in the top right corner of the
EVB in an area marked
“CAN”
3.5 CAN Configuration (J20, J21, J29, J30, J31)
The EVB has 2x NXP TJA1041T high speed CAN transceiver on the MCU CAN-A and CAN-B channels.
These can operate with 5v or 3.3v I/O from the MCU. This is determined by VDDE2 domain. For flexibility, the
CAN transceiver I/O is connected to a standard 0.1” connector and DB9 connector at the top edge of the
PCB. Connectors P11 and P3A provides the CAN bus level signal interface for CAN-A and connector P10 and
P3B for CAN-B. The pinout for these connectors is shown below.
Figure 3-9 CAN Physical Interface Connector
Each of the MCU signals to the CAN transceivers is jumpered, allowing the transceiver to be isolated if that
MCU pin is not configured or used for CAN operation. There is a 2x2 jumper for each CAN channel (one for
Rx, one for Tx). There are also two power jumpers (J30) to physically remove power (12v and 5v) from both of
the CAN transceivers. Jumpers J20 (CAN B) and J21 (CAN A) are configuration jumpers for each of the
Transceivers to control Wake, Standby and Enable. Jumpers can be fitted to select default values or wires
can be used to connect these pins to the MCU.
Table 3-14 CAN Control Jumpers (J30, J31, J7)
Jumper Position PCB Legend Description
J30
Posn 1-2
FITTED (D) 5v is applied to both CAN transceivers VCC
REMOVED No 5v power is applied to CAN transceivers
J30
Posn 3-4
FITTED (D) 12v Power is applied to both CAN transceivers VBAT
REMOVED No 12v power is applied to CAN transceivers
J31 (CAN-A)
Posn 1-2
FITTED (D)
TX
MCU CNTX-A is connected to CAN controller A
REMOVED MCU CNTX-A is NOT routed to CAN controller.
J31 (CAN-A)
Posn 3-4
FITTED (D)
RX
MCU CNRX-A is connected to CAN controller A
REMOVED MCU CNRX-A is NOT routed to CAN controller.
J29 (CAN-B)
Posn 1-2
FITTED (D)
TX
MCU CNTX-B is connected to CAN controller C
REMOVED MCU CNTX-B is NOT routed to CAN controller.
J29 (CAN-B)
Posn 3-4
FITTED (D)
RX
MCU CNRX-B is connected to CAN controller C
REMOVED MCU CNRX-B is NOT routed to CAN controller.
J20 & J21
Posn 1-2
FITTED (D)
WAKE
CAN Transceiver WAKE is connected to GND
REMOVED WAKE is not connected and available on Pin 2
J20 & J21
Posn 3-4
FITTED (D)
STB
CAN Transceiver STB is connected to 5v
REMOVED STB is not connected and available on Pin 4
J20 & J21
Posn 3-4
FITTED
(D)
EN
CAN Transceiver is Enabled
REMOVED EN is not connected and available on Pin 6
Access to the Error and inhibit signals from the transceivers is provided on J33 and J34.
The prototyping area provides features that allow for additional CAN interfaces to be added to the EVB.
Please see Section 6.2 for details.
Notes
-
Care should be taken when fitting the jumper headers as they can easily be fitted in the incorrect
orientation.
HI LOW GND
1