# P1 CAN Loopback #### Items Used * 1x [P1](https://www.macchina.cc/catalog/p1-boards/p1-under-dash) * 1x [OBD3way board](https://www.macchina.cc/catalog/tools/obd3way) * 1x 12V power supply #### OBD3way Setup CAN0H to CAN1H and CAN0L to CAN1L and place a termination resistor across these connections; see photos below for setup. ![](/files/-MAXIu_6aYjLrnGBrEKH) ![](/files/-MAXJ0QKUg-3gM8MdAL4) #### Test Once everything is hooked up, we power up P1, and SSH into P1 in two windows at: 192.168.7.2 to control each CAN channel at the same time. ![](/files/-M2nt2kcKHvosmgl3PF7) Below you can see each session. Note that you'll want to send the "candump ..." command before sending the "cansend ..." command in the other window. {% tabs %} {% tab title="CAN0 Terminal" %} ``` login as: debian Pre-authentication banner message from server: | Debian GNU/Linux 9 | | BeagleBoard.org Debian Image 2019-08-03 | | Support/FAQ: http://elinux.org/Beagleboard:BeagleBoneBlack_Debian | | default username:password is [debian:temppwd] | End of banner message from server debian@192.168.7.2's password: The programs included with the Debian GNU/Linux system are free software; the exact distribution terms for each program are described in the individual files in /usr/share/doc/*/copyright. Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent permitted by applicable law. debian@beaglebone:~$ sudo ip link set can0 type can bitrate 250000 [sudo] password for debian: debian@beaglebone:~$ sudo ifconfig can0 up debian@beaglebone:~$ candump can0 can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD can0 01A [8] 11 22 33 44 AA BB CC DD ^Cdebian@beaglebone:~cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can0 01a#11223344AABBCCDD debian@beaglebone:~$ ``` {% endtab %} {% tab title="CAN1 Terminal" %} ``` login as: debian Pre-authentication banner message from server: | Debian GNU/Linux 9 | | BeagleBoard.org Debian Image 2019-08-03 | | Support/FAQ: http://elinux.org/Beagleboard:BeagleBoneBlack_Debian | | default username:password is [debian:temppwd] | End of banner message from server debian@192.168.7.2's password: The programs included with the Debian GNU/Linux system are free software; the exact distribution terms for each program are described in the individual files in /usr/share/doc/*/copyright. Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent permitted by applicable law. debian@beaglebone:~$ sudo ip link set can1 type can bitrate 250000 [sudo] password for debian: debian@beaglebone:~$ sudo ifconfig can1 up debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ cansend can1 01a#11223344AABBCCDD debian@beaglebone:~$ candump can1 can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD can1 01A [8] 11 22 33 44 AA BB CC DD ``` {% endtab %} {% endtabs %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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