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Explains how to use the MSP430 analog-to-digital converter (ADC).

The analog to digital converter (ADC) on the ez430 is a type called a Sigma-Delta (SD) Converter. The way it operates is slightly different from what was described in the previous section (although the end result is the same) but those specifics are out of the scope of this course. The SD converter on the ez430 has 8 channels and a 16 bit resolution. The module is highly configurable and can run largely free of program involvement. In this portion of the lab, we will broadly explain the features of the module, but the particular effects of each register are listed, as usual, in Chapter 12 of the User’s Guide .

Range of measurement

The result of each conversion will be 16 bits long in the form of an unsigned integer whose value is:

SD16_MEMx (65,536) Vin Vrneg Vrpos Vrneg
Where Vin is the input voltage to be measured, Vrneg is the lower reference voltage, and Vrpos is the higher reference voltage. The reference voltages are set to power and ground by default, but they can be changed to an internal reference generator or an externally supplied reference using the SD16CTL register.

Input channels for the adc

The following is a table of the 8 input channels on the ez430. "Analog signal input" channels will take any analog source (we will get to the pin mapping's shortly). Other channels perform specific tool integrated tasks. For example, channel A6 is an integrated temperature sensor. For detailed descriptions of the others, see the User's Guide .

    Sd16 input channels

  • A0 : Analog signal input
  • A1 : Analog signal input
  • A2 : Analog signal input
  • A3 : Analog signal input
  • A4 : Analog signal input
  • A5 : Vcc Vss 11
  • A6 : Integrated temperature sensor
  • A7 : Short for PGA offset measurement
Here is a pin diagram corresponding to the 14 accessible pins showing which pins correspond to which input channels. Notice that each channel has a "+" and a "-" input. Although with other ADC's, we would simply have one input pin and connect the other to the ground, the SD converter requires us to connect the positive and negative inputs to the corresponding input channels. Note that the numbers from 1-14 on the chip correspond to pins 1-14 on the target board.

Pin map

Shows which pins correspond to specific SD converter inputs. Also shows which pins correspond to specific ports (i.e pin 4 is connected to P1.2).

Operation reminders for the adc

Remember the following when attempting to use the ADC:

  • Be sure to enable SD16 interrupts (on SD16CCTL0 ) and to select the specific channel which you are using (on SD16INCTL )
  • After configuring the ADC, you must enable the SD16SC bit to start conversion.
  • All ADC values will be stored in the SD16MEMx variable where "x" is the number of the channel
The User's Guide will be very useful for this lab because of the complexity of this part of the MSP430. Be sure to go over the chapter atleast briefly before jumping into programming.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
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..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
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da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
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.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
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
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Introduction to the texas instruments ez430. OpenStax CNX. Jun 19, 2006 Download for free at http://cnx.org/content/col10354/1.6
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