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This Lab Module has the project outline for a simple assembly display program. The program is interrupt driven and combines GPIO, polling, and interrupt concepts.

A more complicated assembly program

By now you already have all of the tools you need to complete this assignment. Remember what you have learned about MSP430 assembly language , setting up GPIO , and using interrupts .

  1. Coding in MSP430 assembly, implement an interrupt driven number sequence recorder . You will use the same input configuration from last week (get data from pins 9.4-9.7 on an interrupt from pin 3.7), but now will output a readable loop of the last 5 received numbers in order. Assignment Details

Part ii assignment detail

Your task is to write an assembly program to display a programmable sequence of 5 numbers on the MSP430 ESCAPE Platform.

  • You should use five slots to store the input numbers.
  • Since our simple setup only has one display, you will have to rotate through each of the five numbers after a "short" (in human terms) delay.
  • Use an ISR to store a new number in the "next" slot. (Next not necessarily meaning what is currently being displayed). The input should go from slot 1 to 2 to 3... etc. regardless of which slot is currently being output.
  • The program should only display a slot after a number has been input into it. You will need to keep track of which slots have been filled.
Slot fill chart-- shows how the slots should be filled sequentially.
Only grey boxes are output to the display. Also, notice how after filling all five slots, the ISR loops back and starts filling from the beginning.
Your program should consist of:
  • A setup routine that readies all the components of your program.
  • A main loop that displays the stored numbers one after the other with a readable delay in between.
  • An ISR that stores each new input number to the appropriate slot.

    A few hints:

  • The MSP430 operates at ~13MHz, which may seem slow in terms of computers, but is much too fast for the human eye to process (~30Hz). You will have to implement a very significant delay in between number changes.
  • One way to generate a naive delay is a long loop which does nothing. You may even need to use a nested loop depending on how long of a delay you need.

    Nested Loop Example in C:

    int i=0; int j=0;for (i=0; i<bigNumber; i=i+1) {for(j=bigNumber; j>0; j=j-1) {<!--This code will run ixj times-->; }}
  • You may find it convenient to put your five slots in RAM instead of using registers. You can then store a memory address in the register, and then increment it or set it as needed. You will need to use indirect addressing mode though. mov R4, 0(R15); moves the contents of R4 to the address in R15 mov 0(R15), R4; moves the contents of the address in R15 into R4 mov&0x006300, R4; moves the contents of memory address 0x006300 into R4
  • Consider where it may be useful to implement parts of your program in subroutines


Congratulations on completing lab 4! Your program sophistication has dramatically increased. You understand the basics of interrupt driven programming , and know how to use assembly level subroutines . You have had to keep track of data as well as design a responsive I/O interface to the outside world. Keep up the good work!

Labs based on the original Elec 220 labs maintained by Michael Wu.

Images from original lab documents by Yang Sun. Modified by Matt Johnson.

Questions & Answers

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
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.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
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
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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