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Programming
===========

The RISC-V architecture has a ``gcc`` compiler.
The best reference for getting the correct cross-compiler version is the PicoRV32 source
in the `cliffordwolf/picorv32 repository <https://github.com/cliffordwolf/picorv32>`_.

Specifically, see the top-level ``README.md`` file section
`Building a pure RV32I Toolchain <https://github.com/cliffordwolf/picorv32#building-a-pure-rv32i-toolchain>`_.

For programming examples specifically for the Caravel chip
(assuming a correct installation of a RISC-V ``gcc`` toolchain as described above),
see `efabless/caravel repository <https://github.com/efabless/caravel>`_.

The directory ``verilog/dv`` contains example source code to program the Ravenna chip
along with the header file ``defs.h`` that defines the memory-mapped locations
as described throughout this text.

The ``verilog/dv`` directory contains a ``Makefile`` that compiles ``hex`` files
and runs simulations of a number of test programs that exercise various features of the chip.

Additional documentation exists on the same site for the provided demonstration circuit board and driver software.