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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.


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 (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.


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


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.


firs *AR3+,*AR4+,coefs

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


*(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

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
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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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