Assignment #13
Networking and Communication

One bridge and one node

Video

I chose to make two boards one bridge circuit and one node node circuit. In this video observe how the serial communication between the lap top, the node, and bridge are connected and how they work.

Components:

LED
Microcontroller
Resistor
Capacitor
Phototransistor
ISP header
FTDI headerS

PHASE 1 |Trace

Not to scale

The trace below on the left side is the bridge circuit and the trace on the right is the node circuit.

Now it is time to mill the boards and solder the components to start the network.

PHASE 2 |Process of machining

1- Open the software (Fab Modules), set it on the output format Modela RML and the input format png

2- Insert the interior trace, using the 1/64 inch diameter end mill to mill the electrical traces

3- Fix the board using super glue, or double sided tape

4- Prepare the machine, zero the X, Y, and Z axis, and start milling

5- When you are done with the trace, insert the outer trace to cut the traced circuit from the excess material, using the 1/32 inch diameter end mill

6- Finally, prepare workbench and components

NOTES:

Make sure that the end mill, the bed and the material are fixed otherwise they will vibrate during milling, causing inaccurate tracing and in some cases damaged material.
Double check the end mill type before you start tracing otherwise, if not the proper one for the function, the end mill might break.
After trail and error, I was able to adjust the sufficient depth of milling in the tracing phase in order to come up with clear traces for easier soldering.
Choose a suitable origin for the starting point in order not to wast material.

PHASE 3 |Soldering

Here are the bridge and the node after soldering connected and ready to be programmed.

N.B: Fisrt I need to burn each boar's IC bootloader, and program each separately.

PHASE 4 |Programming

Using Python language

First I need to burn the bootloader of each;
Program each separately;
and finally build the network and serial communication.

Here is the code uploaded successfully

Result

Phython

Here is the serial monitor indicating the given commands

When 0 is pressed the birdge is connected and that is indicated by the LED and when 1 is pressed the node is connected.

Both LEDs blink once indicating a command taken, then one one the LEDs blind according to which commande hace been given 0 or 1.

To see how it works check the video at the top of the page.

mariamwaelgado@gmail.com

http://mariamwaelgado.wix.com/
mariam-wael