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POBest practice to implement fixed byte serial protocol in C++?
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copied!<p>I have a device connected via serial interface to a BeagleBone computer. I communicates in a simple binary format like</p> <pre><code>|MessagID (1 Byte) | Data (n Bytes) | checksum (2 bytes) | </code></pre> <p>The message length is fixed for each command, meaning that it is known how many bytes to read after the First byte of a command was received. After some initial setup communication it sends packets of data every 20 ms.</p> <p>My approach would be to use either termios or something like serial lib and then start a loop doing like that (a:</p> <pre><code>while(keepRunning) { char* buffer[256]; serial.read(buffer, 1) switch(buffer[0]) { case COMMAND1: serial.read(&buffer[1], sizeof(MessageHello)+2); //Read data + checksum if (calculateChecksum(buffer, sizeof(MessageHello)+3) ) { extractDatafromCommand(buffer); } else { doSomeErrorHandling(buffer[0]); } break; case COMMAND2: serial.read(&buffer[1], sizeof(MessageFoo)+2); [...] } } </code></pre> <p>extractDatafromCommand would then create some structs like:</p> <pre><code>struct MessageHello { char name[20]; int version; } </code></pre> <p>Put everything in an own read thread and signal the availability of a new packet to other parts of the program using a semaphore (or a simple flag). </p> <p>Is this a viable solution or are there better improvements to do (I assume so)?</p> <p>Maybe make a abstract class Message and derive the other messages?</p>

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