Differences

This shows you the differences between two versions of the page.

--- litesom:devicetree:can [2017/06/09 21:31]
filug [CAN sender]
+++ litesom:devicetree:can [2017/06/09 22:14]
filug [C/C++ API]
@@ Line 212: / Line 212: @@
 canbusload can0@125000 -r -t -b -c
 </code>
+===== C/C++ API =====
+In case when you want to develop your own application to access CAN bus via ''SocketCAN'' please check [[https://www.kernel.org/doc/Documentation/networking/can.txt|Section 4 in SocketCAN readme]] file.
+In most cases access to the CAN bus looks like access to the ''linux'' interface . Please check //pseudo-code// example presented below.
+<code>
+int s;
+struct sockaddr_can addr;
+struct ifreq ifr;
+/*
+ * Open connection with CAN bus
+ */
+s = socket(PF_CAN, SOCK_RAW, CAN_RAW);
+strcpy(ifr.ifr_name, "can0" );
+ioctl(s, SIOCGIFINDEX, &ifr);
+addr.can_family = AF_CAN;
+addr.can_ifindex = ifr.ifr_ifindex;
+bind(s, (struct sockaddr *)&addr, sizeof(addr));
+/*
+ * build CAN data frame
+ */
+struct can_frame frame;
+frame.can_id = node_id | CAN_EFF_FLAG;  // node id + extended frame format
+frame.can_dlc = 6;                      // data frame length
+frame.data[0] = 0x11;                   // data frame first byte
+frame.data[1] = 0x22;
+frame.data[2] = 0x33;
+frame.data[3] = 0x44;
+frame.data[4] = 0x55;
+frame.data[5] = 0x66;                   // data frame last byte
+/*
+ * send data frame via CAN bus
+ */
+write(s, &frame, sizeof(frame));
+</code>
+===== Python API =====
+Via [[https://buildroot.org|Buildroot]] ''BR2_PACKAGE_PYTHON_CAN'' option located in
+<code>
+-> Target packages
+  -> Interpreter languages and scripting
+    -> External python modules
+      -> python-can
+</code>
+you can build ''python-can'' Python3 package.
+Please read [[https://python-can.readthedocs.io/en/stable/|python-can documentation]] to check how to access CAN from python based application.