Electronics Design
In this assignment we have to do following task.
1.Redraw the hello echo-world board.
2.Add at least one LED and a button (with current limiting resistor)
Schematics.
First step is to re-draw the following board and add a button and LED to it.
To redraw the above circuit i used EAGLE-7.7.0. Click here to download the setup for 32 bit system.
To know about Eagle platform i followed the following links.
https://www.youtube.com/watch?v=1AXwjZoyNno
https://www.youtube.com/watch?v=CCTs0mNXY24
Working on Eagle 7.7.0.
1. Install Eagle, then download fab.lbr (library of components used in circuit) and copy it in the lbr folder of Eagle installation.
2. Similarly download fab.dru (design rules) and place it in the dru folder in the Eagle installation.
3. Switch to Eagle and add components from the library (look for components directly under the Fab folder in the Add Dialog):
4. List of Components
Here is the final Schematic.
Layout
This is how i got the board file when switched from schematic to board
Settings window during autorouting
This is the screen shot of the autorouting options, here since this is a single side simple board we only have to enable the top part and such have to disable the bottom surface by choosing the "N/A" option from the drop down menu. This is how it looks after i added a LED and a switch,i tried both auto and manual routing inorder understand the differance and efficiancy of autoroutung, i felt good with autorouting in eagle but even then at some point of time we may need to manually adjust autorouted one according to our will.
Below you can find the snapshot of the traces of the board.
traces outline
123D Circuits
123D circuits is online pcb designing tool. Visit https://123d.circuits.io/ to use this platform. First make an autodesk account to use this platfrom
Creating schematic is very easy and you just have to click at the pads you want to connect and the connection is drawn with meaningful bends paths. This makes it look neat at the cost of being slightly confusing as some of the lines overlap. You might find it difficult to trace it visually. It allows many cool features like collaborative development options, sharing etc.
While adding components, a quick preview would have been useful,but not to worry these are just a symbolic representation so you dont have to worry a lot about the footprints right away.
Since there is no auto routing option i am still finding out a way how to do routing manually.
Electronics_Production.sch
Electronics_Production.brd
Milling
First step is to create toolpath. I used Aspire 8.0 version to make toolpath.
Problems faced during milling.
Below is the snapshot of the image imported in Aspire.
Tool settings with Flat diameter=0.1 mm. cut depth =0.2 mm
Tool settings with Flat diameter=0.4 mm. cut depth =0.2 mm
Tool settings with Flat diameter=0.6 mm. cut depth =0.2 mm
Tool setting used for outer cut.
Final image of the board.
Stuffing the board.
Testing of board.
Programing the board.
1.For programming the board i will be using arduino 1.8.1.
2.Next step is to download ATtiny addon.
Connect the FabISP to computer and connect the hello FTDI to the ISP using the 6pin header cable.
Follow the following steps for arduino IDE settings.
In Tools go to and pick.
Board-> ATTiny
Processor-> ATtiny 44
Programmer-> usbtinyisp
Clock -> 20Mhz External
Port-> ttyUSB0(if multiple devices are shown you have to figure out which is the port FABISP is connected to)
After settings you should burn the bootloader into the board.
suse Tools->Burn bootloader
The burn succeeded.
Programming
Pin number that arduino ide refers to is not same as attiny pin numbering so look at google for "arduino ide attiny pins". The following is the image I found.
Blink LED
In my hello fdti I have connected the LED to pin 7.
Below you can find the snapshot of the program to blink a LED.
echo Hello World Program
1. Download Neil's echo hello world program. Also download the makefile.Rename the make file from hello.ftdi.44.echo.c.make to "Makefile" without any extension.
2.Connect the ISP to the usb port and connect your board to the ISP. In the terminal move to the location the files are located and now run the following commands in the terminal.
sudo make -f hello.ftdi.44.echo.c.make program-usbtiny
3.After using sudo make -f hello.ftdi.44.echo.c.make program-usbtiny to program the board, with success, finally, I checked the program using a serial port monitor.
4.Connect the FTDI connector to your board and plug it to laptop using usb.
Use dmesg |grip tty to check connection of your board.
Initially terminal prompted an error "FTDI serial device converter disconnected from ttyUSB0". Then to debug it i changed the laptop, and it started working.But after some time again it stopped working with the same error. Then i thought it may be the problem with the cable that was used. So i changed the cable and it started working in both the laptop.
Now to test the program open Arduino and goto serial monitor.
Start giving input in the space provided. But result was not proper. As you can see in the snapshot above some symbols are coming. Then my instructor told me it my be the problem with timing.
Then by changing the baudrate (by seeing it in Neil's program) the output was in characters. Again the problem was it is not following input. FTDI device has ann option to change the output voltage from 3V to 5V. Changing the output volatge to 5V was the solution of my problem.
