Expressions

Many debug commands accept numeric expressions as parameters. A numeric expression is a number or a complex expression that contains numbers, debug objects, or operands. An expression can consist of any of the following components:

Component	Description
Constants	Constants are fixed numeric values or character strings.
System Variables	System variables alter or affect the way µVision4 operates.
Peripheral Variables	Peripheral register variables allow access to the simulated on-chip peripherals.
Program Variables (Symbols)	Program variables are those variables in your target program. They are often called symbols or symbolic names.
Line Numbers	Line numbers reference code addresses of executable programs. When you compile or assemble a program, the compiler and assembler include line number information in the generated object module.
Bit Addresses	Bit addresses reference bit-addressable data memory.
Type Specifications	Type specifications let you specify the data type of an expression or sub-expression.
Operators	Operators include +, -, *, and /. Operators may be used to combine sub-expressions into a single expression. You may use all operators that are available in the C programming language.
Memory Type Specifiers	Memory type specifiers that can be used with debugging commands in 80x51 microcontrollers.
Difference between µVision4 and C	Differences to be aware of.
Expression Examples	Code snippets explaining the usage of expressions you can enter in the Command Window.