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Homework
Our homework was to design and build a wired &/or wireless network connecting at least two processors. I chose to redesign the hellobus bridge and hellobus node boards. This week's assignment was LONG but it went much faster than weeks past because of my experience.

bus

Challenges
  • The bridge board designing was a challenge that took days to figure out. I ended up with some jumpers.
  • Programming presented its challenges but I was able to make some adjustments (see troubleshooting below).

    • Designing
    Eagle is getting easier, but I had difficulties with the bridge board but came up with solutions. The node board was so easy, I even had time to put a fancy "G" for Gail like I see a lot of other board designers do.

    busbus

    Programming

  • It was necessary to change a line in the "c" code before beginning to program so that the bridge (0) and node (1) boards were labeled as 0 and 1 respectively. 
    #define node_id '0'


  • I used the following commands:
    at113@at113m42696:~/hellobus$ sudo make 
at113@at113m42696:~/hellobus$ sudo make program-avrisp2



    Troubleshooting
    I had the polarity backwards on my LED, so I fixed that. When I programmed both the bridge and the node and they were talking to Python, there was a response when I hit ANY number, but no text response. I went back into the code and changed the bit delay time from 100 to 102 and it worked! When I pressed "o", I got one flash indicating that the board got the command to light the light. Then it lit again to "say its name". Very exciting!

    I Learned...
    I learned how these boards talked to one another and the protocol they use. The bridge and node are communicating asyncronously through serial communication using FTDI. I also learned that sometimes you think you have a program you need for programming and you realize you don't, so you have to go get it....AGAIN! Lesson learned: Work on a reliable laptop or machine, THE SAME MACHINE, and keep all of your programs there together so that when you want to program boards, it should go quickly.





    Code and Design Files
    Neil's networking code
    Networking terminal log
    Node board
    Node schematic
    Bridge board
    Bridge schematic