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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

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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