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SP is initialized for you in the core file and should not need to be modified. SP -referenced direct addressing is used by the pshd , pshm , popd , and popm instructions for stack manipulation, as well as by all subroutine calls and returns, which save program addresses onthe stack.

DP -referenced direct addressing is available wherever you see the Smem abbreviation in an assembly syntax description. The advantage of DP -referenced addressing over the *(lk) form described in the next section is that DP -referenced addressing will not add an extra instruction word (and corresponding extra machine cycle). Thedisadvantage is that it is limited to 128 words of contiguous memory, and you have to make sure that DP points to the right 128 words. DP may be changed with the ld instruction as needed.

Examples:

ld 10,A ; sets A = (contents of memory location DP + 10) add 6,B ; sets B = B + (contents of memory location DP + 6)

Make sure you understand that the numbers 10 and 6 above are interpreted as memory addresses, not data values. To get data values, you would need to use a pound sign in front of the numbers.

Absolute addressing: dmad, pmad, *(lk)/smem

This seems to be TI's term for all the forms of direct addressing which it does not call direct addressing! It isrepresented in assembly-instruction syntax-definitions using one of the above abbreviations ( *(lk) addressing is available when the syntax definition says Smem ).

Dmad

dmad (Data Memory ADdress) operands are used by mv xx data move instructions and represent 16-bit memory addresses in datamemory whose contents are used in the instruction.

Example:

f3ptr .word 0 ; reserve one word of storage; initialize to 0 . . . . mvdm f3ptr,AR4 ; set AR4 = memory address of f3ptr

Pmad

pmad (Program Memory ADdress) operands are used by the firs , macd , macp , mvdp , and mvpd instructions, as well as all subroutine calls and branching instructions. They represent 16-bit addresses in programmemory whose contents are used in the instruction, or jumped to in the case of branch instructions. Other thansubroutine calls and branches, the most common use of a pmad is for the firs instruction.

Example:

firs *AR3+,*AR4+,coefs

coefs is a label in the program section of the code, not the data section.

*(lk)

*(lk) addressing is a syntactic oddity. The asterisk symbol generally means that indirect addressing isbeing used (see below), but this is actually direct addressing with a 16-bit data memory address encoded in theinstruction's last word. The reason for the asterisk is that TI does set the "I" bit in the opcode, usually denoting indirect addressing, and this formcan only be used when an Smem is called for in the assembly syntax. Other bits in the low byte of thefirst instruction word tell the processor that the " *(lk) exception" is to be used, and to fetch the memory address in the next word (see the MOD bits onpage 5-10 of the CPU and Peripherals reference). You can easily recognize this addressing mode in .lst files because the low byte of the first instruction word always equals F8h .

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.
Damian
yes that's correct
Professor
I think
Professor
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
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
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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 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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