Texas Instruments MSP50C6xx manual Instruction Syntax and Addressing Modes

Instruction Syntax and Addressing Modes

4.3 Instruction Syntax and Addressing Modes

MSP50P614/MSP50C614 instructions can perform multiple operations per instruction. Many instructions may have multiple source arguments. They can premodify register values and can have only one destination. The addressing mode is part of the source and destination arguments. In the following subsec- tion, a detail of the MSP50P614/MSP50C614 instruction syntax is explained followed by the subsection which describes addressing modes.

4.3.1MSP50P614/MSP50C614 Instruction Syntax

All MSP50P614/MSP50C614 instructions with multiple arguments have the following syntax:

name [dest] [, src] [, src1] [, mod]

where the symbols are described as follows:

name	name of the instruction. Instruction names are shown in bold letters. If the
	instruction name is followed by a B, the arguments are all byte types. If
	name is followed by an S, all arguments are word string (strings of words)
	types. If name is followed by BS, all arguments are byte string types.
dest	destination of data to be stored after the execution of an instruction. Op-
	tional or not used for some instructions. Destination is also used as both a
	source and a destination for some instructions. If a destination is specified,
	it must always be the first argument. Destinations can be system registers
	or data memory locations referred by addressing modes. This is instruc-
	tion specific.
src	source of first data. Optional or not used for some instruction. Source can
	be a system register, a data memory location referred by addressing
	modes, or a program memory location. This is instruction specific.
src1	source of second data. Some instructions use a second data source. Op-
	tional or not used for some instructions. Source 1 can be a system register,
	a data memory location referred by addressing modes, or a program
	memory location. This is instruction specific.
mod	pre or post modification of a register. The meaning of mod is instruction
	specific.
[ ]	Square brackets represent optional arguments. Some instructions have
	many combinations of source and destination registers and addressing
	modes. The combination is instruction class specific.

The possible combinations of sources, destinations and modifications are de- pendent on the instruction class. Instruction classes are discussed in detail in Section 4.4.

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