[miguelangel]

me da este tipo de error..

sketch\CaoDim1C_Lcd20x4.cpp: In member function 'void CaoDim1C_Lcd20x4:rintLnSerBeep(const __FlashStringHelper*, boolean, boolean)':

CaoDim1C_Lcd20x4.cpp:130: error: 'prog_char' does not name a type

const prog_char *p= (const prog_char *)Linea;

^

In file included from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:28:0,

from sketch\CaoDim1C_Lcd20x4.h:11,

from sketch\CaoDim1C_Lcd20x4.cpp:11:

CaoDim1C_Lcd20x4.cpp:135: error: 'p' was not declared in this scope

unsigned char c = pgm_read_byte(p++);

^

sketch\CaoDim1C_Lcd20x4.cpp: In member function 'char* CaoDim1C_Lcd20x4::Fmt(const __FlashStringHelper*, ...)':

CaoDim1C_Lcd20x4.cpp:174: error: 'prog_char' does not name a type

const prog_char *p= (const prog_char *)fmt;

^

In file included from C:\Program Files (x86)\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:28:0,

from sketch\CaoDim1C_Lcd20x4.h:11,

from sketch\CaoDim1C_Lcd20x4.cpp:11:

CaoDim1C_Lcd20x4.cpp:178: error: 'p' was not declared in this scope

unsigned char c = pgm_read_byte(p++);

^

exit status 1
'prog_char' does not name a type
-----------------------------------------------------------------------
arduino 1.8.2
ERROR
const prog_char *p= (const prog_char *)fmt;
Cambiado por:
const char PROGMEM *p = (const char PROGMEM *)fmt;
Solucionado