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Symbolic mode

Symbolic mode allows the assignment of labels to fixed memory locations, so that those locations can be addressed. This is useful for the development of embedded programs.

Description: (PC + X) points to the operand. X is stored in the next word. Indexed mode X(PC) is used.

Source mode bits: As = 01 (memory location is defined by the word immediately following the opcode).

Destination mode bit: Ad=1 (memory location is defined by the word immediately following the opcode).

Syntax: ADDR.

Length: Two or three words.

Comment: Valid for source and destination.

Example 3: Move the content of source address XPT (x pointer) to the destination address YPT (y pointer).

Before operation: XPT=A002h Location YPT=050Ah

Operation: MOV XPT, YPT

After operation: XPT= A002h Location YPT=A002h

Operands 2 nd operand mode Operator Cycles Length (words)
2 Register Any 3 2
2 Indexed, Symbolic or Absolute Any 6 3
1 N/A RRA, RRC, SWPB or SXT 4 2
1 N/A CALL or PUSH 5 2

Absolute mode

Similar to Symbolic mode, with the difference that the label is preceded by “&”.

Description: The word following the instruction contains the absolute address. X is stored in the next word. Indexed mode X(SR) is used.

Source mode bits: As = 01 (memory location is defined by the word immediately following the opcode).

Destination mode bit: Ad=1 (memory location is defined by the word immediately following the opcode).

Syntax: &ADDR.

Length: Two or three words.

Comment: Valid for source and destination.

Example 4: Move the content of source address XPT to the destination address YPT.

Before operation: Location XPT=A002h Location YPT=050Ah

Operation: MOV&XPT,&YPT

After operation: Location XPT= A002h Location YPT=A002h

Operands 2 nd operand mode Operator Cycles Length (words)
2 Register Any 3 2
2 Indexed, Symbolic or Absolute Any 6 3
1 N/A RRA, RRC, SWPB or SXT 4 2
1 N/A CALL or PUSH 5 2

Indirect register mode

The data word addressed is located in the memory location pointed to by Rn. Indirect mode is not valid for destination operands, but can be emulated with the indexed mode format 0(Rn).

Description: Rn is used as a pointer to the operand.

Source mode bits: As = 10.

Syntax: @Rn.

Length: One or two words.

Comment : Valid only for source operand. The substitute for destination operand is 0(Rn).

Example 5: Move the contents of the source address (contents of R4) to the destination (register R5). Register R4 is not modified.

Before operation: R4=A002h R5=050Ah Loc:0xA002=0123h

Operation: MOV @(R4), R5

After operation: R4= A002h R5=0123h Loc:0xA002=0123h

Operands 2 nd operand mode Operator Cycles Length (words)
2 Register Any 2* 1
2 Indexed, Symbolic or Absolute Any 5 2
1 N/A RRA, RRC, SWPB or SXT 3 1
1 N/A CALL or PUSH 4 1

Indirect auto increment mode

Similar to indirect register mode, but with indirect auto increment mode, the operand is incremented as part of the instruction. The format for operands is @Rn+. This is useful for working on blocks of data.

Description: Rn is used as a pointer to the operand. Rn is incremented afterwards by 1 for byte instructions and by 2 for word instructions.

Source mode bits: As = 11.

Syntax: @Rn+.

Length: One or two words.

Comment : Valid only for source operand. The substitute for destination operand is 0(Rn) plus second instruction INCD Rn.

Example 6: Move the contents of the source address (contents of R4) to the destination (register R5), then increment the value in register R4 to point to the next word.

Before operation: R4=A002h R5=050Ah Loc:0xA002=0123h

Operation: MOV @R4+, R5

After operation: R4= A004h R5=0123h Loc:0xA002=0123h

Operands 2 nd operand mode Operator Cycles Length (words)
2 Register Any 2* 1
2 Indexed, Symbolic or Absolute Any 5 2
1 N/A RRA, RRC, SWPB or SXT 3 1
1 N/A PUSH 4 1
1 N/A CALL 5 1

Immediate mode

Immediate mode is used to assign constant values to registers or memory locations.

Description: The word following the instruction contains the immediate constant N. Indirect autoincrement mode @PC+ is used.

Source mode bits: As = 11.

Syntax: #N.

Length: Two or three words. It is one word less if a constant in CG1 or CG2 can be used.

Comment : Valid only for source operand.

Example 7: Move the immediate constant E2h to the destination (register R5).

Before operation: R4=A002h R5=050Ah

Operation: MOV #E2h, R5

After operation: R4= A002h R5=00E2h

Operands 2 nd operand mode Operator Cycles Length (words)
2 Register Any 2* 2
2 Indexed, Symbolic or Absolute Any 5 3
1 N/A RRA, RRC, SWPB or SXT N/A N/A
1 N/A PUSH 4 2
1 N/A CALL 5 2

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Questions & Answers

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 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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
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Source:  OpenStax, Teaching and classroom laboratories based on the “ez430” and "experimenter's board" msp430 microcontroller platforms and code composer essentials. OpenStax CNX. May 19, 2009 Download for free at http://cnx.org/content/col10706/1.3
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