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+ISO-TP (ISO 15765-2) Support Library in C
+================================
+
+This is a platform agnostic C library that implements the ISO 15765-2 (also
+known as ISO-TP) protocol, which runs over a CAN bus. Quoting Wikipedia:
+
+>ISO 15765-2, or ISO-TP, is an international standard for sending data packets
+>over a CAN-Bus. The protocol allows for the transport of messages that exceed
+>the eight byte maximum payload of CAN frames. ISO-TP segments longer messages
+>into multiple frames, adding metadata that allows the interpretation of
+>individual frames and reassembly into a complete message packet by the
+>recipient. It can carry up to 4095 bytes of payload per message packet.
+
+This library doesn't assume anything about the source of the ISO-TP messages or
+the underlying interface to CAN. It uses dependency injection to give you
+complete control.
+
+The current version supports *only single frame ISO-TP messages*. This is fine
+for OBD-II diagnostic messages, for example, but this library needs some
+additional work before it can support sending larger messages.
+
+## Usage
+
+First, create some shim functions to let this library use your lower level
+system:
+
+    // required, this must send a single CAN message with the given arbitration
+    // ID (i.e. the CAN message ID) and data. The size will never be more than 8
+    // bytes.
+    void send_can(const uint16_t arbitration_id, const uint8_t* data,
+            const uint8_t size) {
+        ...
+    }
+
+    // optional, provide to receive debugging log messages
+    void debug(const char* format, ...) {
+        ...
+    }
+
+
+    // not used in the current version
+    void set_timer(uint16_t time_ms, void (*callback)) {
+        ...
+    }
+
+With your shims in place, create an IsoTpShims object to pass them around:
+
+    IsoTpShims shims = isotp_init_shims(debug, send_can, set_timer);
+
+### API
+
+With your shims in hand, send an ISO-TP message:
+
+    // Optional: This is your callback that will be called when the message is
+    // completely sent. If it was single frame (the only type supported right
+    // now), this will be called immediately.
+    void message_sent(const IsoTpMessage* message, const bool success) {
+        // You received the message! Do something with it.
+    }
+
+    IsoTpSendHandle handle = isotp_send(&shims, 0x100, NULL, 0, message_sent);
+
+    if(handle.completed) {
+        if(!handle.success) {
+            // something happened and it already failed - possibly we aren't able to
+            // send CAN messages
+            return;
+        } else {
+            // If the message fit in a single frame, it's already been sent
+            // and you're done
+        }
+    } else {
+        while(true) {
+            // Continue to read from CAN, passing off each message to the handle
+            // this will return true when the message is completely sent (which
+            // may take more than one call if it was multi frame and we're waiting
+            // on flow control responses from the receiver)
+            bool complete = isotp_continue_send(&shims, &handle, 0x100, data, size);
+
+            if(complete && handle.completed) {
+                if(handle.success) {
+                    // All frames of the message have now been sent, following
+                    // whatever flow control feedback it got from the receiver
+                } else {
+                    // the message was unable to be sent and we bailed - fatal
+                    // error!
+                }
+            }
+        }
+    }
+
+Finally, receive an ISO-TP message:
+
+    // Optional: This is your callback for when a complete ISO-TP message is
+    // received at the arbitration ID you specify. The completed message is
+    // also returned by isotp_continue_receive, which can sometimes be more
+    // useful since you have more context.
+    void message_received(const IsoTpMessage* message) {
+    }
+
+    IsoTpReceiveHandle handle = isotp_receive(&shims, 0x100, message_received);
+    if(!handle.success) {
+        // something happened and it already failed - possibly we aren't able to
+        // send CAN messages
+    } else {
+        while(true) {
+            // Continue to read from CAN, passing off each message to the handle
+            IsoTpMessage message = isotp_continue_receive(&shims, &handle, 0x100, data, size);
+
+            if(message.completed && handle.completed) {
+                if(handle.success) {
+                    // A message has been received successfully
+                } else {
+                    // Fatal error - we weren't able to receive a message and
+                    // gave up trying. A message using flow control may have
+                    // timed out.
+                }
+            }
+        }
+    }
+
+## Testing
+
+The library includes a test suite that uses the `check` C unit test library.
+
+    $ make test
+
+You can also see the test coverage if you have `lcov` installed and the
+`BROWSER` environment variable set to your choice of web browsers:
+
+    $ BROWSER=google-chrome-stable make coverage
+
+## Authors
+
+* Chris Peplin cpeplin@ford.com
+* David Boll dboll2@ford.com (the inspiration for the library's API is from David)
+
+## License
+
+Copyright (c) 2013 Ford Motor Company
+
+Licensed under the BSD license.