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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

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.
yes that's correct
I think
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
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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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