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CAN decoder shows wrong values

navymud
Sun, 26 Jun 2022 17:30:08 GMT

I'm using the SQ100 to decode some CAN frames. The frame ID is 0x601 and the CAN message contains the following data: 0x22 0x30 0x01 0x05 0x00 0x00 0x63 0x9C I tried to send this frame using both a Teensy 4.0 (along with a SN65HVD230 transceiver) and an Adafruit Feather M4 CAN. Using both boards, I get an incorrect frame not corresponding at all to the frame I'm sending, with many stuffing errors. *I precise that the second setup (Adafruit board) has proven to work and successfully transmitted the correct frame to a motor controller I'm using.* I configured the first and second channels as differential inputs without pull-down. I attached a screenshot of the beginning of the captured frame. What am I doing wrong? [CAN_frame](//muut.com/u/ikalogic/s3/:ikalogic:cL3L:can_frame.png.jpg)

navymud
Sat, 02 Jul 2022 17:54:29 GMT

I just realized that 0x3FD in binary is the inverse of 0x601. If I try to reverse the probes on CANH and CANL I get nothing at all. Isn't the problem the way the script reads the frame?