Simulators:

• A simulator is the s/w that simulates an h/w unit like emulator, peripheral, network and I/O devices on a PC .

• It defines a processor or processing device as well as various versions for the target system . Monitors the detailed information of as source code part with labels and symbols during the execution for each single step.

• Provides the detailed information of the status of memory RAM and simulated ports, simulated peripheral devices of the defined target system

Emulators:

• An in-circuit emulator (ICE) is a hardware device used to debug the software of an embedded system.

• It was historically in the form of bond out processor which has many internal signals brought out for the purpose of debugging.

• These signals provided information about the state of the processor.

• An in-circuit emulator provides a window into the embedded system. The programmer uses the emulator to load programs into the embedded system, run them, step through them slowly, and view and change data used by the system's software.

• More recently the term also covers JTAG based hardware debuggers which provide equivalent access using on-chip debugging hardware with standard production chips.

• ICE’s attach a terminal or PC to the embedded system. The terminal or PC provides an interactive user interface for the programmer to investigate and control the embedded system.

• In usage, an ICE provides the programmer with execution breakpoints, memory display and monitoring, and input/output control