Each line in a TMS320C28x assembly input file can be empty, a comment, an assembler directive, a macro invocation, or an assembly instruction.

Assembly language source statements can contain four ordered fields (label, mnemonic, operand list, and comment). The general syntax for source statements is as follows:

Labels cannot be placed on instructions that have parallel bars.

Following are examples of source statements:

two     .set  2           ; Symbol two = 2
Begin:  MOV   AR1,#two    ; Load AR1 with 2
        .word 016h        ; Initialize a word with 016h

The C28x assembler reads an unlimited number of characters per line. Source statements that extend beyond 400 characters in length (including comments) are truncated in the listing file.

Follow these guidelines:

• All statements must begin with a label, a blank, an asterisk, or a semicolon.
• Labels are optional for most statements; if used, they must begin in column 1.
• One or more space or tab characters must separate each field.
• Comments are optional. Comments that begin in column 1 can begin with an asterisk or a semicolon (* or ;), but comments that begin in any other column must begin with a semicolon.

The following sections describe each of the fields.