1.5 is a complete rewrite of the IO-56 software. A single application is used for all extensions. The source code is also much clearer and more modular. IO-56 expects options on the command line.
Some options are global to all modules, and some are specific to one module.
Global options are expected after the extension name, specific options are expected after global options, and commands are expected after specific options. All lines of the ISA card are configured as output. Output signals can be checked using a multimeter. The NES extension is still primitive. I tried to write some data, and read it back, to test if VRAM is present, but it seems that this can mess up the MMC, and bank switching does not work anymore after this test until next reset.