System Variables

System variables allow accessing specific functions and can be used anywhere program variables or expressions can be used. The system variables are listed in the table below.

System Variable	Type	Description
$	unsigned long	Represents the program counter. Use the $-sign to display and change the program counter. For example, `$ = 0x4000` sets the program counter to the address 0x4000.
_break_	unsigned int	Halts program execution when set to a non-zero value. Use this variable in debug functions to halt program execution.
_traps_	unsigned int	Displays messages for the 166 hardware traps when set to a non-zero value. 166-Hardware traps: Undefined Opcode, Protected Instruction Fault, Illegal Word Operand Access, Illegal Instruction Access, Stack Underflow and Stack Overflow.
states	unsigned long	Displays the CPU instruction state counter value. It starts counting from 0 and increments with each executed instruction.
seconds	double	Displays execution time in seconds. This variable is available for some devices.
itrace	unsigned int	Indicates whether trace recording is performed. When itrace is 0, no trace recording is performed. When itrace has a non-zero value, trace information is recorded. Refer to Instruction Trace Window.
radix	unsigned int	Displays and sets the output base for numeric values. radix can be 10 or 16. The default setting is 16 for HEX output. Change the output base by entering `radix=10` in the Command window.