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Do not use an asterisk in front of ARx variables here, since this is not indirect addressing.


mvmm AR3,AR5 ; sets AR5 = AR3 stm #5,AR2 ; sets AR2 = 5 ldm AR0,A ; sets A = AR0

Immediate addressing: #k3, #k5, k, #k9, #lk

Immediate addressing means that the numerical value of the data is itself provided within the assemblyinstruction. Various TMS320C54x instructions allow immediate data of 3, 5, 8, 9, or 16 bits in length, which are signifiedin the assembly language syntax descriptions with one of the above symbols. The 16-bit form is the most common and issignified by #lk . 16-bit immediate values always require an extra instruction word and therefore take an extramachine cycle to execute.

An immediate data operand is almost always specified in assembler syntax by prepending a pound sign ( # ) to the data. Depending on the context, the assembler mayassume that you meant immediate addressing anyway.


ld #0,A ; sets A = 0 cmpm AR1,#1 ; sets flag TC = 1 if AR1 == 1; else TC = 0

Labels make this more complicated. Recall that a label in your assembly code is nothing more than shorthand for thememory address where the labeled code or data is stored. So does an instruction like

stm coef,AR2 ; sets AR2 = memory address of label coef

mean to store the contents of memory location coef in AR2 , or does it mean to store the memory address coef itself in AR2 ? The second interpretation is correct. Because the stm instruction has only one form, expecting a #lk immediate operand, the assembler does not care whether the label is prefixed with a pound signor not. Still, it would have been better for us to include the pound sign in the above example for clarity.

Many instructions have several versions allowing the use of different addressing modes (see ld for a good example of this). With these instructions, including thepound sign is not optional when specifying immediate addressing. The only safe rule, then, is always to prefix thelabel with a pound sign if you wish to specify the memory address of the label and not the contents of that address.

If you are not sure how a particular instruction has been assembled, you can always examine the .lst file produced by the assembler, and compare the hexadecimal opcodeslisted to the left of the assembly instructions with the assembly opcodes given in the assembly language manual(Chapter 4 of the Mnemonic Instruction Set reference).

Direct addressing: smem and others

In the modes called direct addressing by TI, the instruction opcode contains a memory offset (see the "dma"bits on page 5-8 of the CPU and Peripherals reference) seven bits long, which is combined with either the DP (data pointer) or SP (stack pointer) register to obtain a complete 16-bit data-memory address. This divides the data memory intopages of 128 words each.

Questions & Answers

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
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
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.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket 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, Ece 320 - spring 2003. OpenStax CNX. Jan 22, 2004 Download for free at http://cnx.org/content/col10096/1.2
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