Week 12: Networking and communications

This week I wanted to display alternating prime numbers by passing one number from the mother board to the node board via serial bus communication and displaying the numbers on python. FOr example, if mother board sends 5, the node board finds the next prime that is 7. I made my shcmeatic based on Neil's board for Serial bus communication. I didn't include LEDs in this week.

Eagle board for the mother:

Traces and outline:

Schematic followed by Eagle board and traces_outline of node board:

Mother board and node board after soldering:

I wanted to implement the basic program of communicating 0 and 1 from the keyboard and when received by the respective nodes: Mother node_id 0 and node node_id 1, the python interfaces display espective node names. Although the boards were simple, I had to do lot of troubleshooting this week. It started with the serial bus cable, I didn't press the pins properly while making the cable. I figured out using a multimeter that the two ends of Serial bus cable are not connected to the pins well enough!

Once I solved that I was able to display node 0, I couldn't get the node 1 working. I had troubleshoot again for the next couple of days. I finally figured out that one my solders wasn't shiny for the ISP header. Hence, the clock pin of node 1's ISP header was not working. It wasn't connected to the node at all. When I resoldered it, then the node started working.

By the end of the week after a lot of troubleshooting with simple boards, I could implement basic program of diplaying node numbers when the numbers are pressed on the keyboard.

I went on to program my boards to communicate the prime numbers from one node to the other. Although I could find the prime numbers individually in for loops, I was not able to send the characters from one board to the other.

Here are the codes I used to program the boards.

hello.bus.44.c.

hello.bus1.44.c.

hello.temp.44.py.