Xin Wen

How to Make (almost) Anything

Week 13: Networking and Communications


1. Following the Example
2. My Own Design

This week's assignment is to build a wired and/or wireless network connecting at least two processors. For my final project, I needed to connect four parts to the interface so I decided to start with the Neil's example serial bus boards. I was going to modify it to connect four separate boards (the input devices).


1. Following the Example

My soldering skill has improved quite a lot over the course of the semester. For the Neil's serial bus example boards, I was able to program the two nodes on the first try. When I tried to program the bridge board, I got the dreaded "initialization failed, rc=1" error but I was able to fix it by resoldering leads of the processor.

Figure 1. Node boards programmed.
Figure 2. Bridge board programmed.
Figure 3. Connected!
2. My Own Design
For my own boards, I didn't have a processor on the bridge board because all it does is to connect the node boards to the computer. So I just had a ftdi connector and 2x2 header to connect to the rest of the boards. The code for the communication can be found on my final presentation page. All the boards are connected serially with the computer and has its unique ID. Once the computer sends out a node ID, the board with the node ID will do something and echo back its ID (mostly so that I know it works).
Figure 4. Bridge schematic.
Figure 5. Bridge board.
Figure 6. Node schematic.
Figure 7. Node board.