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When the ADC10 ends the conversion, an interrupt is requested. While variable min is lower than 60, the temperature is written to flash memory. The memory pointer is increased by two (word). When min = 60 , the system stops operation.

System configuration

Dco configuration

Adjust the DCO frequency to 1 MHz by software using the calibrated DCOCTL and BCSCTL1 register settings stored in information memory segment A.

if (CALBC1_1MHZ == 0xFF || CALDCO_1MHZ == 0xFF) {while(1); // If calibration constants erased // do not load, trap CPU!!}DCOCTL = CALDCO_1MHZ; // Set DCO to 1 MHz

Basic clock module+ configuration

Set MCLK and SMCLK to 1 MHz. Use the internal very low power VLOCLK source clock to ACLK/8 clock signal as low frequency oscillator (12 kHz):

BCSCTL1 = DIVA_3; // ACLK = 1.5 kHz BCSCTL3 = LFXT1S_2; // Set VLOCLK (12 kHz)

Adc10 configuration

The ADC10’s input channel is the integrated temperature sensor (A10) and it uses the signal V REF+ (1.5 V) as reference voltage. The ADC10 clock source is ADC10OSC, the clock signal being ADC10CLK/4. Configure the ADC10 sample-and-hold time: 64xADC10CLKs, to perform a single-channel single-conversion and enable its interrupts. What are the values to write to the configuration registers?

ADC10CTL1 = INCH_10 + ADC10DIV_3; // Temp Sensor (A10), // ADC10CLK/4,// clock source: ADC10OSC ADC10CTL0=SREF_1 + ADC10SHT_3 + REFON + ADC10ON +ADC10IE;// Internal reference voltage Vref+ = 1.5 V // ADC10 sample-and-hold time: 64 x ADC10CLKs// Reference-generator voltage = 1.5 V // ADC10 on + ADC10 interrupt enable//*********************************************************// ADC10 Interrupt Service Routine //*********************************************************#pragma vector=ADC10_VECTOR __interrupt void ADC10ISR(void){ unsigned int temperature; if (min<= 60) {temperature = ((ADC10MEM - 673) * 423) / 1024; write_int_flash(memo_ptr,temperature);memo_ptr += 2; }else {_NOP(); }}

Timer_a configuration

Configure Timer_A register to enable an interrupt once every second. Use the ACLK clock signal as the clock source. This timer is configured in up counter mode in order to count until the TAR value reaches the TACCR0 value.

TACCTL0 = CCIE; // TACCR0 interrupt enabled TACCR0 = 1500; // this count corresponds to 1 secTACTL = TASSEL_1 | MC_1 | ID_0;// ACLK, up mode to TACCR0//********************************************************** // Timer_A Interrupt Service Routine//********************************************************** #pragma vector=TIMERA0_VECTOR__interrupt void TimerA0_ISR (void) {counter++; P1OUT ^= 0x01; // LED toogleif (counter == 60){ min++;counter = 0; ADC10CTL0 |= ENC + ADC10SC; // Sampling/Conversion start} }

Analysis of operation

After compiling the project, start the debug session and before running the application, put a breakpoint at the line of code with the _NOP() instruction. Go to breakpoint properties and set action to Write data to file . Name the file as Temp.dat and define the data format as integer . The data starts at address 0x01040 , with a length of 3C . Run the application and let the temperature data logger acquire the values for 1 hour. Use a heater or a fan to force temperature variations during the measurement period. When execution reaches the breakpoint, the file will be available in your file system. Construct a graph in Excel or a similar tool, in order to plot the temperature variation obtained by the data logger.

This example and many others are available on the MSP430 Teaching ROM.

Request this ROM, and our other Teaching Materials here (External Link)

Questions & Answers

general equation for photosynthesis
Ojasope Reply
6CO2 + 6H2O + solar energy= C6H1206+ 6O2
Anastasiya
meaning of amino Acids
AJAYI Reply
a diagram of an adult mosquito
mubarak Reply
what are white blood cells
Mlungisi Reply
white blood cell is part of the immune system. that help fight the infection.
MG
what about tissue celss
Mlungisi
Cells with a similar function, form a tissue. For example the nervous tissue is composed by cells:neurons and glia cells. Muscle tissue, is composed by different cells.
Anastasiya
I need further explanation coz celewi anything guys,,,
Calvin Reply
hey guys
Isala
on what?
Anastasiya
hie
Lish
is air homogenous or hetrogenous
damiane Reply
homogenous
Kevin
why saying homogenous?
Isala
explain if oxygen is necessary for photosynthesis
Allice Reply
explain if oxygen is necessary for photosynthesis
Allice Reply
Yes, the plant does need oxygen. The plant uses oxygen, water, light, and produced food. The plant use process called photosynthesis.
MG
By using the energy of sunlight, plants convert carbon dioxide and water into carbohydrates and oxygen by photosynthesis. This happens during the day and sunlight is needed.
NOBLE
no. it s a product of the process
Anastasiya
yet still is it needed?
NOBLE
no. The reaction is: 6CO2+6H20+ solar energy =C6H12O6(glucose)+602. The plant requires Carbon dioxyde, light, and water Only, and produces glucose and oxygen( which is a waste).
Anastasiya
what was the question
NOBLE Reply
joining
Godfrey
the specific one
NOBLE
the study of non and living organism is called.
Godfrey
Is call biology
Alohan
yeah
NOBLE
yes
Usher
what Is ecology
Musonda Reply
what is a cell
Emmanuel Reply
A cell is a basic structure and functional unit of life
Ndongya
what is biolgy
Hawwi Reply
is the study of living and non living organisms
Ahmed
may u draw the female organ
MARTIN Reply
i dont understand
Asal
:/
Asal
me too
DAVID
anabolism and catabolism
Sani Reply
Anabolism refers to the process in methabolism in which complex molecules are formed "built" and requires energy to happen. Catabolism is the opposite process: complex molecules are deconstructed releasing energy, such as during glicolysis.
Anastasiya
Explain briefly independent assortment gene .
Otu Reply
hi
Amargo
hi I'm Anatalia
Joy
what do you mean by pituitary gland
Digambar
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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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