Differences

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--- can_interfaces [2024/03/09 19:08] – created river
+++ can_interfaces [2025/02/02 15:30] (current) – river
@@ Line 1: / Line 1: @@
 ====== CAN Interfaces ======
-USB CAN adapters can show as follows on Linux.
+USB CAN adapters can appear as follows on Linux.
+===== SocketCAN =====
+A can network device appears. e.g. can0, shown by ifconfig.
+Set bitrate for NMEA2000 and bring up CAN interface:
+''ip link set can0 up type can bitrate 250000''
+It seems SignalK doesn't do this itself.
+[[https://www.kernel.org/doc/html/v5.11/networking/can.html|Kernel SocketCAN docs]]
 ===== Serial Line CAN =====
-A serial port appears. slcand can talk to it.
+Some USB to CAN adapters may run a firmware that presents as a CDC-ACM serial port, e.g. CANable devices. **slcand** can talk to the devices over the virtual serial port and create a standard SocketCAN device, at which point you can continue the same as with a native SocketCAN adapter.
-===== SocketCAN =====
+''slcand -o -s5 /dev/ttyACMx''
-A can network device appears. e.g. can0, shown by ifconfig.
+The -s arguments sets the CAN bus speed:
+<file>
+    -s0 = 10k
+    -s1 = 20k
+    -s2 = 50k
+    -s3 = 100k
+    -s4 = 125k
+    -s5 = 250k
+    -s6 = 500k
+    -s7 = 750k
+    -s8 = 1M
+</file>
+===== Analysers =====
+==== Canboat ====
+Install Linux SocketCAN tools:
+''sudo apt install can-utils''
+Configure SocketCAN interface:
+''ip link set can0 up type can bitrate 250000''
+Use canboat analyzer tool:
+''candump can0 | candump2analyzer | analyzer''
+==== Wireshark ====
+Can open SocketCAN interfaces, like ''can0''. Select ''Analyze -> Decode As'', and in the last column of the table you can click to set it to ''J1939''. This will decode as far as giving you PGNs. I didn't find an NMEA2000 decoder, but this at least tells you data is flowing.
+===== Hardware =====
+==== CANable ====
+CANable is a USB - CAN interface using an STM32F072. CANable firmware does slcan. The same device can be flashed with candleLight firmware which does Linux native / SocketCAN. I bought a device from Aliexpress which came with candleLight.
+[[https://www.aliexpress.com/item/1005006032351087.html]]
+==== Waveshare Pico CAN ====
+[[waveshare_pico_can|Waveshare Pico CAN]]
-[[https://www.kernel.org/doc/html/v5.11/networking/can.html]]
+==== NMEA2000 - USB Interface ====
+[[ngt-1|Actisense NGT-1]]
-CANable is a USB - CAN interface using an STM32F072. CANable firmware does slcan. candleLight firmware does Linux native / SocketCAN.