Failed to connect to STLink V3 using CAN

[Hyang.21]

Hello,

I want to program an STM32F429 with STLINK-V3SET using CAN.STLINK-V3SET.

When I connect the PB5 pin (CAN_RX) and PB13 pin (CAN_TX) of the STM32F429 to the CAN_RX and CAN_TX of CN5 on STLINK-V3SET, the connection can be successful(as shown in figure 1).

figure 1

However, when I connected two CAN transceivers (ADM3503) between STM32F429 and STLINK-V3SET, in theory it should be able to connect successfully, but it actually failed to connect (prompt connection timeout).As shown in figure 2 is the connection diagram I drew,are there any errors? and why it can't work?

figure 2

Then I found there have another interface to using CAN from UM2448(as shown in figure 3),but it still did not work,when I connected the outputs CAN_RX and CAN_TX of the ADM3503 to the CAN_TX and CAN_RX pins of CN9 on STlink-V3SET, respectively.

Another question is, I used a multimeter to measure that CAN_TX of CN5 and CN9 are connected, but CAN_RX is not connected. What is the reason?

figure 3

Has anyone used this feature?Please answer my doubts

Thank you,

Best regards,

Huayu Yang

[Pjaco.1]

The CAN pins on CN5 do not require a CAN transceiver. If you look at the V3 manual you'll see that if CN5 is selected (with jumper JP7) then the signals on CN5 are T_CAN_TX (presumably this indicated transceiver CAN TX) and T_CAN_RX.

Using the CAN Tx and Rx on CN7 and CN9 both require the use of an external CAN receiver, whereas this is not the case on CN5.

[Pjaco.1]

whoops - I meant to say an external CAN transceiver, not receiver.

[GhostSherry]

Goodday Hyang.21, I was wondering if you were able to solve this? If so, could you please share how you eventually figured it out?