Week 3 Day2
Many of the fabacademy cad items are design that have .cad extension. These were designed in kokopelli. .cad file is basically a python script. Today we try to edit and understand how the script ad kokopelli.

Assignment
We add components to a hello.ftdi.44.cad and wires on a board and fabricate it.

Process
The following were attempted in kokopelli on hellofdti cad file downloaded
Adding components
Position components
Add traces
Increase board length
Reposition elements
Rewire
I downloaded the hello ftdi files from fabarchieve from the links.
 http://academy.cba.mit.edu/classes/embedded_programming/hello.ftdi.44.cad
 http://academy.cba.mit.edu/classes/embedded_programming/hello.ftdi.44.png
Experimenting Commenting and uncommenting the lines from line number 20 onwards allow us to get desired out put.


From line 5593 onwards where "#define board " starts we can change the parameters like width of line, board width and length etc.
The code goes like 
#
# define board
#

w = .016
width = 1
height = .93
mask = .004
x = 1
y = 1
z = -.005
d = .06

 It is not recommend below for trace width(w) to be lesser than 0.012. Assign intelligent values for these parameter and let it remain default unless theres a problem. 

Design
The following editions were committed in the file. this code is added under #define board and before #select ouput. The PCB had trouble with placingthe 6mm push button, hence we had to resize the board make it wide and reposition IC. Code:

# define board
#

w = .016
width = 1.2
height = .93
mask = .004
x = 1
y = 1
z = -.005
d = .06


....Uneditted code
.
.
 # repositioned the IC. Every other element seems to                                                  #positioned relative to the ic.

pcb = wire(pcb,w,    IC1.pad[13],
   point(IC1.pad[13].x+.105,J2.pad[4].y,z),
   J2.pad[4])
.
.
.

 #adding led
LED1=LED_1206('Led')    #usually the format is like component_size('name')
pcb= LED1.add(pcb,XTAL1.x,IC1.pad[5].y,z,180) #showing the led
 
R2=R_1206('R2\n1k')    #adding resistor and naming it "R2 1k"
pcb= R2.add(pcb,LED1.pad[2].x,LED1.y-0.15,z,-90)

B1=button_6mm('B1')   #adding push button
pcb=B1.add(pcb,LED1.x+0.2,J1.y+0.05,z)

pcb = wire(pcb,w,         #adding traces
   IC1.pad[5],
   LED1.pad[1])

pcb = wire(pcb,w,
   LED1.pad[2],
   R2.pad[1])

pcb = wire(pcb,w,
   J1.pad[6],
   R2.pad[2]
   )
pcb = wire(pcb,w,
   IC1.pad[6],
   B1.pad[4]
   )
pcb = wire(pcb,w,
   J1.pad[6],
   B1.pad[3]  
   )

Exporting as .png
(make sure you name the file with the extension or else the export wont work and throw an exception)

Machining 

Machining parameter
Milling output
 
Final Output after stuffing with components.