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Usb power to busses

show power from pins 1 and 14 on the Launchpad to the + and - busses
Notice the color choice of wires. For the rest of the construction process, the short green and blue wires are only used for connections to GND and Vcc respectively.

5) connect your switches to gnd

Use the green jumper wires to connect the other side of your switches to GND (the blue bus). Yes, the switch pack is upside down . This is an intentional design decision that has to do with the pull-up configuration of the MSP430 Launchpad Hardware. With the switch pack upside down, flipping the switch "up" will register a "1" and flipping them "down" will register a "0" like you would expect. See the explanation below for more information, or just take it on faith that it works this way.

Switches to gnd

connect the open end of the DIP switch to VCC

You may notice that turning the switch on connects it to GND, but turning it off connects it to nothing! This can be really bad in a circuit- the values read from the GPIO pins will be essentially random! Ideally, you would want your switches to be "1" when up and "0" when down. To accomplish this, you can either use more expensive dual pole switches that switch between two connections instead of closing or breaking just one, or use what's called a pull up (or pull down) resistor. This is a resistor of large resistance connected to the rail you want the switch to read when it is open. The GPIO sees most of the connected voltage when the switch is on (and in digital applications most is enough), but sees the other rail when the switch is open.

"But I see no resistors in the picture"-- you're right! The MSP430 has pull up resistors built in- we just have to enable them when we configure the GPIO pins. You'll learn more about that in part II of the lab.

6) connect vcc and ground to ics

The BCD decoder is an active piece of circuitry, so it needs a power connection to work properly. Connect Vcc to pin 16 (lower A-E column 21) and GND to pin 8 (lower F-J column 28) .

The display also needs a common connection to ground (since it is common cathode type). Connect pin 3 (lower F-J column 38) to GND. The display is just a package of individual LED's in parallel connected to one common ground point.

Lastly, there are some options (dealing with latching and enabling) on the decoder we want to permanently set in our circuit. Connect Vcc to pins 3 and 4 (lower F-J columns 23 and 24) and GND to pin 5 (lower F-J column 25).

Power connections for circuit components

shows Vcc to decoder pins 1, 13, and 14 and ground to decoder pins 9 and 12 and display pin 8
Notice how the color scheme of blue jumpers for Vcc and green jumpers for GND continues here. It's good practice to use a consistent color scheme for Vcc and GND since they can fry your chips if mis-applied.

7) connect the decoder to the resistor arrays

Our resistor arrays

The resistor arrays used in this class contain 4 isolated 470 ohm resistors. We could have just as easily used individual resistors, but this keeps the breadboard clean and prevents accidental shorting from the uninsulated resistor leads. Every pair of pins in the strip works as if there is a 470 ohm resistor in between them, but each pair exists on its own. I.E. there is a resistor in between pins 1 and 2 but nothing between 2 and 3.

Questions & Answers

how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
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Maciej
Do somebody tell me a best nano engineering book for beginners?
s. Reply
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Devang Reply
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
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Cied
what is biological synthesis of nanoparticles
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what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
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Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
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Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
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Prasenjit Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Intro to computational engineering: elec 220 labs. OpenStax CNX. Mar 11, 2013 Download for free at http://cnx.org/content/col11405/1.2
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