CRT files are binary images of C64 cartridges. They contain additional header data providing additional details, i.e. which address. space the cartridge occupies. most of downloadable cartridge files in the internet are in this format.
There is very good description of the file format at Codebase64
CRT files are binary images of C64 cartridges. They contain additional header data providing additional details, i.e. which address. space the cartridge occupies. most of downloadable cartridge files in the internet are in this format.
There is very good description of the file format at Codebase64