Texas Instruments MSP50C614 manual Assembler Directives, Examples, ~ indicates bitwise complement

Assembler

5.7.2Assembler Directives

Assembler directives are texts which have special meaning to the assembler. Some of these directives are extremely helpful during conditional compiling, debugging, adding additional features to existing codes, multiple hardware development, code release etc. Other directives are an essential part of the assembler to initialize variable with values, assigning symbols to memory location, assigning origin of a program, etc. The assembler directives that start with a # (hash) sign cannot have spaces before the directive. The following assembler directives are recognized by the assembler. Some of these assembler directives uses expression and symbol. These are explained below:

expression can be any numeric value. Addition, subtraction, and multiplication are allowed.

Examples:

(128 / 2 ) * 2 + (220 / 5) + 2 + *0x200 equates to 0xAE + *0x200, where *0x200 indicates data memory location.

(2 * 2 / 2 + ((5 * 2) * 3) / 2) (0x0F & 0x04) equates to 0x15. Note that bitwise AND (& operator) and OR ( operator) operation is allowed.

(10 * 2) + 5 * *0x120 expression points to data memory content at 0x120 and multiplies decimal 5 to it and finally adds decimal 20. Note that a space is required between successive asterisks (*). Also note that *0x120 indicates content of memory location at 0x120 hex.

The grammer for expression and symbol is as follows:

number:	number 0 1 2 3 4 5 6 7 8 9
expression:	number
	expression + expression
	expression ± expression
	expression * expression
	expression / expression
	expression expression
	expression & expression
	~expression
	±expression
	+expression
	*expression
	(expression)

(~ indicates bitwise complement)

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