This file contains an overview of the C16 runtime system as it comes with the cc65 C compiler. It describes the memory layout, C16/116 specific header files, available drivers, and any pitfalls specific to that platform.
Please note that C16 specific functions are just mentioned here, they are described in detail in the separate function reference. Even functions marked as "platform dependent" may be available on more than one platform. Please see the function reference for more information.
Since the C16/C116 and the Commodore Plus/4 are almost identical (the former don't have the 6551 ACIA and only 16KB of memory), the Plus/4 documentation is also worth a look. The difference between both cc65 targets is that the Plus/4 runtime uses banking to support full 64K RAM, while the C16 does not use banking and supports up to 32K RAM. Because banking is not needed, most C16 programs will be somewhat smaller than the same program compiled for the Plus/4. However, programs C16 will always run on the Plus/4, while the reverse is not necessarily true.