lesto:
in teoria se metti la define prima di tutto nel tuo .ino non funziona lo stesso?
C'è scritto di metterlo prima dell'include... e così ho fatto
/**
\ingroup avr_pgmspace
\typedef prog_char
\note DEPRECATEDThis typedef is now deprecated because the usage of the progmem
attribute on a type is not supported in GCC. However, the use of the
progmem attribute on a variable declaration is supported, and this is
now the recommended usage.The typedef is only visible if the macro PROG_TYPES_COMPAT
has been defined before including <avr/pgmspace.h> (either by a
#define directive, or by a -D compiler option.)Type of a "char" object located in flash ROM.
*/
typedef char PROGMEM prog_char;