How to Make Almost Anything > John's class Homepage > efe: Capacitive Sensing
Efe: Capacitive Sensing
We
take the efe board and change the board and code to get a better idea of
capacitive sensing, circuit design, and the ATTINY15. ·
There’s a general
move to using the vinyl cutter to make circuit boards. I watched people try
to make it work for a few hours today. Not encouraging. ·
Changing the circuit
board: o
I decided to add a
USB connector to the board in place of the mini-molex because: ·
My final project will
involve many efe/type simple microcontroller circuits networked together. ·
I am imagining users
continually plugging and unplugging these circuits from each other. ·
The connectors to be
easy for the user to use i.e.
big and tough. ·
Off-the-shelf cables
with connectors would be a big time saver for me. ·
Note: I am not
using the USB protocol. Just the connector. o
I chose to remake the
circuit in Protel and alter it in that environment: ·
Make the components 1. is there a way to rotate components? 2. make the “bulb” of the pin stick away from the chip 3. rotate with the <space> bar 4. Why am I getting “node not found” errors using the
LED part? 5. question on capacitor orientation 6. what a mess of names everywhere on the PCB after re-laying out the board in Protel I found that cam.py doesn’t
accept Protel Gerber. I played around with editing the Gerber file and with
editing cam.py, then switched to Eagle. o
Using eagle ·
When I make changes
to the Schematic, how do I update the board? ·
How do you connect
components? o
Soldering: ·
A great trick for
soldering surface mount resisters etc.: 1. Put a dab of solder on one of the pads 2. put the resister on top of the pads. Press down on
the resister and heat the pad w/ the solder ·
Don’t touch the
solder w/ the soldering iron…the solder just evaporates. o
Using the Modella ---
a review: ·
To cancel, go into view
mode and hit the up and down buttons at the same time. When the
job is cancelled, the light will flash quickly. ·
Use move <x>
<y> to move the modella to coordinates. 1 1 is 2 squares in and 2
squares back. ·
With the bit loose,
move the modella to its furthest position down. Then move it up slightly,
then tighten the bit. So the bit is resting on the board w/ the modella
slightly higher than it’s lowest position. ·
Type cam
<filename> to run cam.py. (Why doesn’t python cam.py
<filename> work?) ·
Set the X and Y
offsets in CAM to be the same as where I want the board to be made. ·
From cam.py choose
<contour boundary>, <raster interior>, <write toolpath> ·
Good values: 1. Z up = .05 2. Z down = -0.015 3. XY speed 2 4. Z speed 2 5. tool diameter .-156 6. contour undercut 0 7. raster overlap .8 (or try a tighter overlap next
time.) |
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