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WEEK 6

ELECTRONICS DESIGN (WEEK 1 OF 2)


Assignment:
Redraw the echo hello-world board and add at least a button
and LED with current-limiting resistor or design your own.

What I used for this assignment
Machine:
- Roland monoFab SRM-20, to mill the PCB

Material:
- soldering tools and components

Softwares:
- Eagle, from CadSoft editor, CAD-Software for PCB design
- ArduinoIDE, for the programming
- Fab Modules, to prepare the files for the Roland (.rml)
Here are the output files for this assignment:
First board files (Eagle Schematic and board files, .png file)
Final board files (Eagle Schematic and board files, .png file, .rml files)


DETAILS

The Echo Hello-World Board (sources)

The aim is to re-draw the Echo Hello-World Board
In order to do this, my sources were the following:

Source images:

Model of Microcontroller: ATMEL ATTINY44A-SSU 8 Bit Microcontroller,
Low Power High Performance, ATtiny, 20 MHz, 4 KB, 256 Byte, 14, SOIC
Here is the page with all information about it on farnell.com website
Including the Technical DataSheet ... oups ... 286 pages for the full version!! ;-)

Installing Eagle software, and starting using it

After installing the Eagle software,
and the libraries (from SparkFun, and Fab Academy)
now I can start using the software doing the 'simple led schema'

First we create a project, and then we start to do the Schematic
Here is my Schematic for the 'simple led schema'
We can test it with the ERC (Electrical Rule Check) when finished

Then we switch to the Board view
and we start to design the board
first we move the components to the Board...

and then we do the routing between components

In order to create a groundplane we have to draw a polygon around the Board

And then using the Ratsnest function, it will automaticaly create the groundplane

Now doing the Echo Hello-World board (First Version)

Here is my final Eagle Schematic
It includes the Button (switch) and the led+resistor schema
connections to VCC and GND are not optimized, I should have used the copy feature to simplify with several VCC and GND objects, next time I will do it :-)

Here is my final Eagle Board
I created 2 polygons (one for VCC, one for GND), in order to minimize the drilling job

After applying Ratsnest
and all layers displayed

After applying Ratsnest
and only top layer displayed

An example of interface will adding a component in Schematic view

My configuration: Libraries, Design Rules (including MySettings.dru which is my resulting settings, inspired from SeeedStudio dru)...

As a result, here is my PCB schema (.png export from Eagle)
First version of my Hello Board Design

Milling and soldering the Echo Hello-World board (Final Version)

Working in Fabmodule
configuring

Here is preview of path

I had to minimize width of 1 trace
because I got an error on Roland (that was not identify with the DRC in Eagle)

On the Roland
configuring X/Y/Z zero

On the Roland
selecting file for the job

My friend Roland is milling ;-)

Boards milled, on the left the one with Error on 1 trace, on the right the final one

Here is the Final Version of my Hello-World Board
more "aerated"

Milled and soldered version