ArdweeNET forum

BUSnet (old version of this network, no longer active) => General => Topic started by: Graynomad on January 30, 2011, 04:23:14 PM

Title: Simple MCU requirements
Post by: Graynomad on January 30, 2011, 04:23:14 PM
The full BUSnet spec is a bit daunting at first and even I get put off by the amount of work to do. But a simple proof of concept shouldn’t be difficult so I’ll try to document what I think needs doing here.

To get things started here’s some initial thoughts on what a very simple MCU has to do.

  • Communicate with a PC via serial, presumably using USB over a bridge cable.
  • Maintain an array of Point Definition Tables (PDTs).
  • Scan the PDTs at regular intervals to get Node addresses, and then pole the Nodes.
  • Place any input values in the Node’s PDT.
  • Action commands from the PC: either return a value from a Node’s PDT or send a command to a Node.

That should be about it to get started, initially no handling of timeouts, errors or anything, just get a basic protocol working.