Tms320c54 Assembly

8/2/2019 Tms320c54 Assembly

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TMS320C54XX INSTRUCTIONS &

PROGRAMMING

Load & Store Instructions:

Load Instructions

1. LD Load Acc with shift The LD instruction loads the acc with a

data memory value or an immediate value

This instruction supports different shiftquantities.

Also supports acc to acc moves with shift


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Syntax:

1. LD Smem, dst

2. LD #lk, dst

2. LDM: Load acc from a MMR.

LDM MMR, dst

3. Load TREG/DP/ASM/ARP The load inst.

Loads a value into TREG or into thefollowing fields of the status register:DP,ASM,ARP


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Store Instructions:

ST Store TREG, TRN or immediatevalue into memory

1. ST T, Smem

2. ST TRN, Smem3. ST #lk, Smem

STH Store acc high into memory1. STH src, Smem

2. STH src, ASM, Smem

3.

STH src, SHIFT1, Xmem


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STL Store acc low into memory

1. STL src, Smem2. STL src,ASM, Smem

STLM Store acc low into MMRSTLM src, MMR

STM Store immediate value into MMR

STM #lk,MMR


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Conditional Store Inst : CMPS, STRCD

Parallel Load & Store Inst : ST||LDParallel Load & Multiply Inst :LD||MAC

Parallel Store & add/subtract Inst :

ST||ADD, ST||SUBParallel Store & Multiply Inst : ST||MAC,

ST||MPY

Misc Load type & store type Inst: MVDD,MVPD


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Arithmetic Operations

Add Inst : ADD, ADDC

Subtract : SUB, SUBB

Multiply : MPY, MPYA Multiply & Accumulate : MACD, MAC

Multiply & Subtract : MAS, MASA


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Logical Operations

AND Inst : AND, ANDM

OR : OR, ORM XOR : XOR, XORM

Shift : ROL, SFTL

Test : BIT, CMPM


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Program Control Instructions:

Branch Inst : B, BACC

Call : CALL, CALA

Interrupt : INTR, TRAPReturn : RET, FRET

Repeat : RPT, RPTB

Stack : PUSHD, POPD

Miscellaneous : IDLE, RESET


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ASSEMBLER DESCRPITION

The assembler translates assemblylanguage source files into machinelanguage object files.

Source files can contain the followingassembly language elements:

i. assembler directives

ii. macro directives

iii. assembly language instructions


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The assembler does the following:

i. processes the source statements in a textfile to produce a relocatable C54x objectfile

ii. Allows to segment the code into sectionsand maintain a section program counter(SPC) for each section of object code

iii. Defines and references global symbolsiv. Assembles conditional blocks


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Naming alternate files & directories for

assembler input:i. The .copy, .include and .mlib directivestell the assembler to use code fromexternal files.

ii. The .copy and .include directives tell theassembler to read source statementsfrom another file, and the .mlib directive

names a library that contains macrofunctions.

Syntax: .copy filename


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Source Statement Format:

TMS320C54x assembly language sourceprograms consist of source statementsthat can contain

i. assembler directives

ii. assembly language instructions

iii.

macro directivesiv. comments


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Source Statement Syntax

A source statement can contain four orderedfields.

Mnemonic Syntax:

[label][:] mnemonic [operand list] [;comment] All statements must begin with a label, a

blank, an asterik or a semicolon.

A statement containing an assemblerdirective must be specified entirely on oneline.


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Labels are optional; if used, they mustbegin in column 1

One or more blanks must separate eachfield.

Tab characters are equivalent to blanks

Comments are optional. Comments thatbegin in column1 can begin with anasterik or a semicolon, but comments thatbegin in any other column must beginwith a semicolon


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Label Field Labels are optional for all assembly language

instructions and for most assemblerdirectives.

A label must begin in column 1 of a source

statement. A label can contain up to 32 alphanumeric

characters (A-Z,a-z,0-9,_ and $).

Labels are case sensitive, and the firstcharacter cannot be a number.

A label can be followed by a colon, the colonis not treated as part of the label name.


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If a label is not used, the first characterposition must contain a blank, asemicolon, or an asterik.


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Mnemonic Instruction Fields:

In mnemonic assembly, the label field isfollowed by the mnemonic and operandfields.

Mnemonic Field:

This field follows the label field.

This field must not start in column 1; if itdoes, it will be interpreted as a label.


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It can contain one of the following

opcodes: machine instruction mnemonic (ABS,

STH)

assembler directive (.data, .list) macro directive

macro call


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Operand Field

The operand field is a list of operands thatfollow the mnemonic field.

An operand can be a constant, a symbol,or a combination of constants and symbolsin an expression

The assembler allows to specify that aconstant, symbol or an expression shouldbe used as an address, an immediatevalue, or an indirect value.


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Comment Field

A comment can begin in any column andextends to the end of the source line.

A comment can contain any ASCIIcharacter, including blanks.

A source st. that contains a comment aloneis valid.

Comments that begin in column1 can

begin with an asterik or a semicolon, butcomments that begin in any other columnmust begin with a semicolon


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Assembler directives Assembler directives supply data to the

program and control the assembly process.Assembler directives enable you to do thefollowing:

Assemble code and data into specifiedsections

Reserve space in memory for uninitializedvariables

Assemble conditional blocks Declare global variables

Specify libraries from which the assembler

can obtain macros


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Directives that define sections

.bss symbol, size in words [, blocking][, alignment ]Reserve size words in the .bss (un initializeddata) section

.data Assemble into the .data (initialized data)

.sect section name Assemble into a named(initialized) section

.text Assemble into the .text (executable code)

sectionsymbol .usect section name, size in words

[, blocking] [,alignment] Reserve size words in a

named (un initialized) section


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Directives that initialize constants (data andmemory)

.bes size in bits Reserve size bits in thecurrent section; note that a label points tothe last addressable word in the reserved

space .byte value1 [, ..., valuen] .char value1 [, ..., valuen] Initialize one or

more successive words in the current

section .double value1 [, ... , valuen] .ldouble value1 [, ... , valuen] Initialize

one or more 64-bit, IEEE double-

precision,floating-point constants


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.double value1 [, ..., valuen]

.ldouble value1 [, ..., valuen] Initialize oneor more 64-bit, IEEE double-precision,floating-point constants

.int value1 [, ..., valuen] Initialize one ormore 16-bit integers 4-67

.longvalue1 [, ..., valuen] Initialize one or

more 32-bit integers


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Directives that reference other files

.copy []filename[] Include sourcestatements from another file

.def symbol1 [, ..., symboln] Identify one ormore symbols that are defined in the

current module and may be used in othermodules

.global symbol1 [, ..., symboln] Identify oneor more global (external) symbols

.include []filename[] Include sourcestatements from another file


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Directives That Define SectionsThese directives associate portions of anassembly language program with the

appropriate sections: .bss reserves space in the .bss section for

uninitialized variables. .data identifies portions of code in the .data

section. The .data section usually containsinitialized data.

.sect defines initialized named sections andassociates subsequent code or data withthat section. A section defined with .sectcan contain executable code or data.


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.text identifies portions of code in the .text

section.The .text section usually contains

executable code.

.usect reserves space in an uninitializednamed section.

The .usect directive is similar to the .bss

directive, but it allows to reserve spaceseparately from the .bsssection.


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1 ************************************************** 2 * Start assembling into the .text section *

3 ************************************************** 4 000000 .text 5 000000 0001 .word 1,2 000001 0002 6 000002 0003 .word 3,4 000003 0004 7 8 ************************************************** 9 * Start assembling into the .data section * 10 ************************************************** 11 000000 .data

12 000000 0009 .word 9, 10 000001 000A 13 000002 000B .word 11, 12 000003 000C 14


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15 ************************************************** 16 * Start assembling into a named, * 17 * initialized section, var_defs *

18 ************************************************** 19 000000 .sect var_defs 20 000000 0011 .word 17, 18 000001 0012 21

22 ************************************************** 23 * Resume assembling into the .data section * 24 ************************************************** 25 000004 .data 26 000004 000D .word 13, 14 000005 000E 27 000000 .bss sym, 19 ; Reserve space in .bss 28 000006 000F .word 15, 16 ; Still in .data 000007 0010 29


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30 **************************************************31 * Resume assembling into the .text section *32 **************************************************33 000004 .text34 000004 0005 .word 5, 6000005 000635 000000 usym .usect xy, 20 ; Reserve space in xy

36 000006 0007 .word 7, 8 ; Still in .text000007 0008


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.text initializes words with the values 1, 2, 3, 4, 5,6, 7, and 8.

.data initializes words with the values 9, 10, 11,12, 13, 14, 15,and 16.

.bss reserves 19 words.

.usect reserves 20 words. The .bss and .usect directives do not end the

current section or begin new sections; they

reserve the specified amount of space, and thenthe assembler resumes assembling code or datainto the current section.

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Tms320c54 Assembly