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- Interrupts.

Software application organization

The software structure allows various tasks to be performed simultaneously. The routine main() is responsible for configuring all the resources used by the application. Once started, the application enables all the interrupts and waits for an interrupt request.

There are two routines that separately service the two possible interrupts. The routine TimerA1_ISR() services interrupts required by the Timer_A overflow and by the TACCR1 capture unit. For every interrupt caused by a TACCR1 capture, the value collected in the TACCR1 register is stored in T1 , if it is the first low-to-high transition, or stored in T2 if it is the second low-to-high transition. This sequence is controlled by the variable capture. The variable flag is used to flag the measurement process. This process occurs between the capture of the first low-to-high transition and the second transition. The counting of clock pulses is done by Timer_A, in the time interval between the T1 and T2 acquisition, assigned to the variable T . The process is synchronized when Timer_A overflows, restarting the measurement process. The LCD is refreshed once every 0.5 seconds with the latest measured frequency value, using the control variable control tick that corresponds to 0.5 seconds.

The routine basic_timer_ISR() services the interrupt produced by Basic Timer1 once every second. This routine begins by switching the state of LED1 and LED2. In addition, it updates the Timer_B counting period. The variable read_data allows the counting period to be changed.

System configuration

Basic timer1

Basic Timer1 generates an interrupt once every second. Use the two counters in series, where the BTCNT2 counter input is selected as the BTCNT1 counter output divided by 256. The BTCNT1 counter input is the ACLK clock signal with a frequency of 32.768 kHz.

If BTCNT2 counter selected output is divided by 128, what is the time period associated with the Basic Timer1 interrupt? _________

The values written to the configuration registers are:

BTCTL = BTDIV | BT_fCLK2_DIV128; // (ACLK/256)/128 IE2 |= BTIE; // Enable BT interrupt with 1 sec period

Timer_b

The TBCCR4 compare unit is used to generate the PWM signal. The set/reset compare mode is used.

The values written to the configuration registers are:

TBCTL = TBSSEL_2 | CNTL_0 | TBCLGRP_0 |MC_1 | ID_0; // SMCLK, continuous modeTBCCTL4 = OUTMOD_3; // CCR4 output mode 3 (set/reset)

The TB4 PWM output signal has a frequency X, with a 50% duty-cycle. The SMCLK clock signal is used as input of Timer_B.

The values written to the configuration registers are:

TBCCR0 = 39977;// Output 200 Hz signal with 50% duty cycle TBCCR4 = TBCCR0/2;

What the largest and lowest generated frequency?

Maximum frequency value: ____________

Minimum frequency value: _____________

Timer_a

Timer_A is sourced by the SMCLK clock signal. It counts to the value 0xFFFF, in continuous mode. An interrupt is generated when the TAR counter overflows. What is the value to write to its configuration register?

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
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
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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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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