Guido
First a Forum Comment: You started this in the tinyG/TinyG Feature Requests sub-forum. Now that I see where you are headed, I believe you should be in the tinyG/TinyG Support sub-forum. It is likely that more active developers, like yourself, will see your posts and respond. This sub-forum is sort of a wish list for future features, the Support sub-forum is for “how-do-I-make-it-work”. I suggest you continue there,
Your project: I believe your description of an implementation of Xon/Xoff protocol is a good one. BUT it implies to me that your environment on the PIC32 has minimal ‘driver’ like support for peripherals, since flow control, buffering, etc. are usually handled by device drivers. Your approach seems correct, but readers here can only assume that your implementation has also considered any possible error cases and recovery from them.
Have you run your CNC via a terminal application running on a PC under Windows (or Linux, or MacOS)? A very typical environment that most here understand and use is Coolterm on Windows. Running some test Gcode from that platform will reveal the steps necessary to Run a complete job. In general, you first need to configure tinyG with tinyG specific configuration commands(such as setting the Flow control to Xon/Xoff, or RTS/CTS, or….) and configure tinyG for specifics about your machine (motor setup, axis setup). All these steps are covered on the wiki, start here
I continue to believe you can implement your PIC based machine controller, but I am not sure you have a grasp on all the steps necessary for success. Since there is no detailed how-to to guide you, the experience you would gain from running a complete (successful) job via Coolterm would seem a hands on introduction to the complete process.
For most folks here, running tinyG from a terminal is the “lowest level” interface and most work with higher level applications such as tgFX or Chilipeppr or JCNC.
Many folks have coded their own implementations, but you are really on your own to understand all the pieces of the puzzle
When you continue, I do suggest switching to tinyG Support sub-forum. You will attract more input there.
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