The standard Or1ksim ISS incorporates the functionality of several common peripherals. The objective of this application note is to demonstrate the ISS driving external peripherals modeled in SystemC using TLM 2.0 interfaces.

Or1ksim peripherals are configured in a textual configuration file, with a section (introduced by the keyword section) for each device attached. This configuration file specifies the memory mapped addresses of the peripheral. Any reads or writes to those addresses will be directed to the code of the peripheral within Or1ksim.

Or1ksim is extended with a new class of peripheral, generic, which specifies an external peripheral. The specification in the configuration file specifies the memory mapped address range covered and whether byte, half word or full word access are enabled. Multiple generic sections may be defined (for different address ranges) in the configuration file.

Code is added to Or1ksim, so that any read or write to a generic peripheral is redirected back to the wrapper code via the upcalls specified as arguments to or1ksim_init (see Section 4.1.1 and Section 4.2.6).