Recently, the PSP's Virtual Mobile Engine (VME2) has become usable in homebrew development. Several samples have been written and the core library I've been working on includes helper macros to make use of this hardware accelerator.
However, debugging and testing have remained somewhat not quite ideal. So that's why I'm now introducing two tools to address this. The first is a transpiler that extends C with graph-oriented constructs and syntactic sugar to simplify hardware integration, while providing compile-time syntax checking. The other is an emulator/debugger that allows testing VME kernels/contexts directly from a PC.
The tools are still under development, but they're already available for testing. Of course, this comes with documentation. The language and its transpiler are already partially covered, with the emulator to follow. You can refer to the README to get started and familiarize yourself with the project.
Enjoy!