Zilog Z8F0130 - Manual (Page 266)

Using the ANSI C-Compiler UM013037-1212
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Zilog Developer Studio II – Z8 Encore!
User Manual
or far data, or, if the pointer is to const data, in ROM. The naming of these functions is
straightforward, as follows:
If foo(void* p1,const void* p2) is a standard library function taking parameters
pointing to the default memory space, then the following the following additional library
functions are defined:
•
f_f_foo(far void* p1, const far void* p2) takes pointers to far (12-bit)
memory
•
f_n_foo(far void* p1, const near void* p2) takes pointers to far (12-bit)
memory and near (8-bit) memory
•
f_r_foo(rom void* p1, const near void* p2) takes pointers to far (12-bit)
memory and rom (read-only 16-bit) memory
•
n_f_foo(near void* p1, const far void* p2) takes pointers to near (8-bit)
memory and far (12-bit) memory
•
n_n_foo(near void* p1, const near void* p2) takes pointers near (8-bit)
memory
•
n_r_foo(near void* p1, const near void* p2) takes pointers to near (8-
bit) memory and rom (read-only 16-bit) memory

There are no r_X_foo() variants, because the first parameter to foo() is not const .
foo is #defined to either n_n_foo or f_f_foo depending on memory model, but the
unadorned foo() function still exists in the run-time library.
In most cases, the return type must be the type of one of the parameters. One special case
is the
malloc() function, which takes only a size_t parameter. In addition to mal-
loc() , there is an f_malloc() , which allocates from far memory, and n_malloc() ,
which allocates from near memory.
Finally, the standard format strings for printf() , scanf() and their variants are
enhanced by providing a syntax to specify that a pointer parameter points into near, far, or
rom memory:
"%Ns" formats or reads a string in near memory.
"%Fs" formats or reads a string in far memory.
"%Rs" formats or reads a string in ROM memory.
"%Np" formats a pointer to near memory.
"%Fp" formats a pointer to far memory.
"%Rp" formats a pointer to ROM memory.
"%Nn" saves the number of characters generated so far to an integer in near memory.