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3

Assuming the dysfunctional star topology is already in place and you don't have very tight real-time requirements, you could perhaps patch together what you have with this solution: At the central node, place one CAN transceiver and a 120R terminator. At each node, another CAN transceiver and a 120R terminator. Mux the CANH CANL lines to one node at a time, ...


2

Star-shaped networks are generally not recommended, but 20m stubs on a starshaped RS485 should be fine, assuming you keep under ~38400 baud and not go much beyond 10 sensors.


1

Pete W answered with the help of the following link : http://www.cse.dmu.ac.uk/~eg/tele/CanbusIDandMask.html The solution was a filter for 0x300 and a mask of 0x1FFFFF00


1

If you want as many as 9 out of 13, then acceptance masking is pretty pointless. It is generally an overrated feature of CAN from the time before "mailbox" CAN controllers were invented. The main use of masking is when you expect a whole lot (hundreds) of identifiers on the bus that you aren't interested in. Acceptance masking tends to make things ...


1

The first thing you must do is to fix your incorrect connector pin-out and turn it into CAN. DB9 connectors for CAN are widely standardized and professional engineers follow industry standards. You should have CANHI=7, CANLO=2, GND=3. Once you have turned your pin-out into CAN, the simplest solution might be to buy pre-made DB9 terminators and plug those in ...


1

CAN transceivers are "dumb", you don't really commuicate with them but rather through them. The task of the CAN transceiver is to translate the Tx and Rx signals from the controller (logic voltage levels) into a differential signal consisting of CANHI and CANLO with +/- 2.5V levels. In this case, MPC56 are 3V3 so you will need a 3V3 tolerant ...


1

CAN controller talks with CAN PHY with TX and RX pins. Look up any CAN PHY tranceiver datasheet. Unless the MCU has a built-in CAN PHY, no it is not possible to connect to a CAN bus without a CAN PHY.


1

What you describe is static PDO mapping, which is also in my experience the most common. Every PDO is mapped to a data entry in the object dictionary, no matter if it is static or not. You always have PDO mapping settings and those settings point out where in the OD the PDO should read/store data at. In case you are following one of the standardized Device ...


0

I think you have to use SDO messages in your case. If you want to try mapping a parameter for example: voltage , to object dictionary entries then you have to send a SDO write message so this link Will give you more information on it


0

Problem Solved ! I did'nt really found why it was not working on my first prototype but I faced the same issue with my final PCB. However there was a short circuit between the CAN TX and RX on one MCU due to a thin wire of tin ! Even with that problem i had the RX signal on my scope that's why i did'nt thought it was a hard problem ! I removed the bad ...


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