# Interfaces

This chapter describes the following interfaces provided with the
simulator:

- [Timer interface](https://docs.qualcomm.com/doc/80-N3040-23/topic/timer-interface.html#simulator-timer-interface) - Used by a
target application to collect execution statistics on specific parts
of its own code.
- [Cache interface](https://docs.qualcomm.com/doc/80-N3040-23/topic/cache-interface.html#simulator-cache-interface) - Used by a
target application to maintain the processor cache while it is being
simulated.
- [Application programming interface (API)](https://docs.qualcomm.com/doc/80-N3040-23/topic/system-interface.html#simulator-system-api) - Used by client programs to control
simulations without user input.
- [API callbacks](https://docs.qualcomm.com/doc/80-N3040-23/topic/callbacks.html#simulator-callbacks) - Set up and used via
API calls.

Both the Timer interface and Cache interface are DSP domain utility
libraries. They are to be linked in when building the target ELF to
be simulated. Their effects come from the simulation.

The API operates in the host domain to make the simulator more
versatile by customization. Its effect is on the simulation host. If
you do not plan to build a customized simulator, the Simulator System
API is irrelevant.

Last Published: Oct 06, 2026

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