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Using the MSP-EXP430FG4618 Development Tool and the MSP430FG4618 device implement a voltage ramp generator Basic Timer1.

Laboratory dac: lab1 - voltage ramp generator

Introduction

This laboratory gives an example of the use of the DAC available in the MSP-EXP430FG4618 Development Tool. The DAC module reference is obtained from the ADC module. The DAC is configured with 12 bits resolution in straight binary format. The DAC’s output value is updated every 1 msec by a Timer_A ISR. The buttons SW1 and SW2 are used to manually modify the DAC’s output.

Overview

This laboratory ( Lab1_DAC.c )implements a voltage ramp generator. The DAC module reference is obtained from the ADC module. The DAC is configured with 12-bit resolution, in straight binary format. The output of the DAC value is updated once every 1 msec by an interrupt service routine (ISR) generated by Timer_A. The push buttons SW1 and SW2 are used to manually modify the output of the DAC value. When the microcontroller is not performing any task, it enters low power mode.

Resources

The DAC12_0 module uses V REF+ as reference voltage. It is therefore necessary to activate this reference voltage in the ADC12 module.

The DAC12_0 is connected to Port P6.6 on the Header 8 pin 7. Connect the oscilloscope probe to this port pin.

The output of the DAC is updated whenever Timer_A generates an interrupt. This peripheral is configured to generate an interrupt with a 1 msec time period.

After refreshing the output of the DAC, the system returns to low power mode LPM3.

The push buttons SW1 and SW2 allow the output of the DAC value to be changed manually.

The resources used by the application are:

- Timer_A;

- DAC12;

- I/O ports;

- FLL+;

- Interrupts.

Software application organization

The application starts by stopping the Watchdog Timer.

Then, the ADC12’s reference voltage is activated and set to 2.5 V. A delay is used to allow the reference voltage to settle. During this time period, the device enters low power mode LPM0. The delay period, which is controlled by Timer_A, enables an interrupt when it completes. The interrupt wakes the device and proceeds with the execution of the application.

Timer_A is reconfigured to generate an interrupt once every 1 msec. This interrupt service routine (ISR) updates the output of the DAC.

Ports P1.0 and P1.1 are connected to buttons SW1 and SW2. The ports are configured as inputs with interrupt capability, such that the ISR can decode which button is pushed. If the interrupt source is due to button SW1, then the output of the DAC is increased. If the interrupt source is due to button SW2, then the output of the DAC is decreased.

System configuration

Fll+ configuration

FLL_CTL0 |= DCOPLUS | XCAP18PF; // DCO+ set, // freq = xtal x D x N+1SCFI0 |= FN_4; // x2 DCO freq, // 8MHz nominal DCO SCFQCTL = 121; // (121+1) x 32768 x 2 = 7.99 MHz

Reference voltage selection

The DAC12_0 uses the signal V REF+ as reference voltage. What is the value to write to the configuration register in order to obtain the internally available reference?

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
Abhi
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
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ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
hmm
Abhi
is it a question of log
Abhi
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Abhi
I rally confuse this number And equations too I need exactly help
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salma
Commplementary angles
Idrissa Reply
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Sherica
im all ears I need to learn
Sherica
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Tamia
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Uday
hi
salma
what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
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Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Al
y=10×
Embra Reply
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rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
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how do you translate this in Algebraic Expressions
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Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
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. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
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what's the easiest and fastest way to the synthesize AgNP?
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China
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types of nano material
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I start with an easy one. carbon nanotubes woven into a long filament like a string
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many many of nanotubes
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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
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what is system testing?
AMJAD
preparation of nanomaterial
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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
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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
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how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
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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can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
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the Beer law works very well for dilute solutions but fails for very high concentrations. why?
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how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Teaching and classroom laboratories based on the “ez430” and "experimenter's board" msp430 microcontroller platforms and code composer essentials. OpenStax CNX. May 19, 2009 Download for free at http://cnx.org/content/col10706/1.3
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