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Although the first LDW instruction do not load the A4 register correctly while the ADD is executed, the D1 functional unit becomes available in the clock cycle right after the one in which LDW is executed.

To clarify the execution of instructions with delay slots, let's think of the following example of the LDW instruction. Let's assume A10 = 0x0100 A2=1 , and your intent is loading A9 with the 32-bit word at the address 0x0104 . The 3 MV instructions are not related to the LDW instruction. They do something else.

1 LDW .D1 *A10++[A2], A92 MV .L1 A10, A8 3 MV .L1 A1, A104 MV .L1 A1, A2 5 ...

We can ask several interesting questions at this point:

  1. What is the value loaded to A8 ? That is, in which clock cycle, the address pointer isupdated?
  2. Can we load the address offset register A2 before the LDW instruction finishes the actual loading?
  3. Is it legal to load to A10 before the first LDW finishes loading the memory content to A9 ? That is, can we change the address pointer before the 4 delay slotselapse?
Here are the answers:
  1. Although it takes an extra 4 clock cycles for the LDW instruction to load the memory content to A9 , the address pointer and offset registers ( A10 and A2 ) are read and updated in the clock cycle the LDW instruction is issued. Therefore, in line 2, A8 is loaded with the updated A10 , that is A10 = A8 = 0x104 .
  2. Because the LDW reads the A10 and A2 registers in the first clock cycle, you are free to change these registers and do not affect the operationof the first LDW .
  3. This was already answered above.

Similar theory holds for MPY and B (when using a register as a branch address) instructions. The MPY reads in the source values in the first clock cycle and loads themultiplication result after the 2nd clock cycle. For B , the address pointer is read in the first clock cycle, and the actual branching occurs after the5th clock cycle. Thus, after the first clock cycle, you are free to modify the source or the address pointer registers.For more details, refer Table 3-5 in the instruction set description or read the description of the individualinstruction.

Addition, subtraction and multiplication

There are several instructions for addition, subtraction and multiplication on the C6x CPU. The basic instructions are ADD , SUB , and MPY . ADD and SUB have 0 delay slots (meaning the results of the operation are immediately available), but the MPY has 1 delay slot (the result of the multiplication is valid after an additional 1 clock cycle).

(Add, subtract, and multiply): Write an assembly program to compute ( 0000 ef35h + 0000 33dch - 0000 1234h ) * 0000 0007h

Branching and conditional operations

Often you need to control the flow of the program execution by branching to another block of code. The B instruction does the job in the C6x CPU. The address of the branch can be specified either bydisplacement or stored in a register to be used by the B instruction. The B instruction has 5 delay slots, meaning that the actual branch occurs in the 5th clock cycleafter the instruction is executed.

Questions & Answers

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
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
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
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Dsp lab with ti c6x dsp and c6713 dsk. OpenStax CNX. Feb 18, 2013 Download for free at http://cnx.org/content/col11264/1.6
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