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The code perspective and writing code

Code Composer supports assembly code, “classic” C, and C++. For this class we will focus on assembly code and standard C. Most of your coding will happen in the coding perspective, a view where the screen is dominated by a massive text editing window. Code Composer’s editor can be setup in a range from straight forward wyswig to auto-tabbing, auto-highlighting, and auto-completing. Again, explore the options (window→preferences) and find what works best for you and your lab partner.

Writing assembly:

To write assembly in Code Composer, you first need to create a new project following the steps above (be sure to select “ Empty Assembly-only Project ”!). Once you have your empty project, insert a new file (file → new → file). When you input the file name, be sure to give it an “ .asm ” extension. Now that you have your freshly created asm file, you can start writing code in the code window (the big blank white space in the middle of the screen). In assembly mode, code composer parses the column most left as labels, so any non-label code must be indented at least one tab (and conversely labels cannot be indented). You will learn more about the specific components required for a functional assembly file in your specific labs, but in general, you need five common lines. The first, “.cdecls C, LIST, “msp430g2231.h”” defines all of your programming constants (such as P1IN, WDTCTL, etc.). The second “.text” tells the assembler where your actual code begins. The label “RESET” goes at the start of your program so the hardware knows where to begin code execution after a power reset. At the end of your code, you need to leave the memory address of your reset label. To do this, use the command [.sect “.reset”] to tell the compiler you are in the reset section, and then [.word RESET]to place the address of the RESET label into memory.

Writing c:

Code composer really shines writing C and C++. Like in assembly, you will need to create a new project for your new program. This time leave “treat as an assembly-only project” unchecked. Now you will create a new “c source file” (file→ new → source file). When you input the file name this time, be sure to give it a “ .c ” extension. In c mode, you don’t have to worry about line spacing or tabbing for the functionality of the program, just your own sanity and code readability. To include the file you used in the .asm projects that defined all the hardware constants, put the line “ #include “msp430g2231.h” ” at the top of your code. You won’t have to worry about the reset vector or anything like that—the c compiler will take care of it all for you. The only thing actually required in your c program is the function “ void main() {… YOUR CODE… } ”. Other more advanced operations (like interrupts) require special c syntax, but you will cover that in the specific labs when it comes up.

Debug mode, stepping, breakpoints, and watches

Debug mode differentiates an IDE like CCS4 from simpler command line tools. For better or for worse, simply pressing the debug button magically translates your source code into a running program on your attached MSP430. You will notice that after the debugger finally starts up though, your code will not actually be running. This is because the debugger starts in step mode with the first line of your code highlighted. In other words, the hardware is waiting for you to let it execute that one line of code, so your slow human reflexes can process and verify what it can do in a fraction of a second. Stepping through your code one line at a time helps you find subtle errors and see exactly where a program goes off track. Yes, as you can imagine, simply stepping through a real world multi-thousand line program (or the larger programs you will write later in this course) is inefficient and unfeasible. Breakpoints allow you to tell the debugger to stop if/when the processor gets to a certain point in your code, letting you run quickly through the code you trust and only stop at certain problematic sections you want to look into more closely. You can set several breakpoints at once, and once the program has broken, you will be able to actively see all register and memory values and step through line by line just as if you had started step mode at your break point. Watches are a little bit more abstract and more useful for larger programs, but they allow you to set a watch on a particular variable (in c) or memory location/register (in asm) and only break the program when it tries to change that particular value. This can help you find where exactly where and when a value changes into an erroneous state.

Using a combination of breakpoints, watches, and careful stepping, you can pick apart any complicated program to hunt down errors and really understand what goes on during the program’s execution.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
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
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
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, Intro to computational engineering: elec 220 labs. OpenStax CNX. Mar 11, 2013 Download for free at http://cnx.org/content/col11405/1.2
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