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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

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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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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