- /* Macros: */
- #if !defined(__DOXYGEN__)
- #define _GETADCMUXMASK2(x, y) x ## y
- #define _GETADCMUXMASK(x, y) _GETADCMUXMASK2(x, y)
+ #if defined(USB_SERIES_4_AVR) && ((VTARGET_ADC_CHANNEL == 2) || (VTARGET_ADC_CHANNEL == 3)) && !defined(NO_VTARGET_DETECT)
+ #error The U4 AVR chips do not contain ADC channels 2 or 3. Please change VTARGET_ADC_CHANNEL or define NO_VTARGET_DETECT in the makefile.
+ #endif
+
+ #if defined(VTARGET_USE_INTERNAL_REF)
+ #undef VTARGET_REF_VOLTS
+ #define VTARGET_REF_VOLTS 2.56
+
+ #define VTARGET_REF_MASK ADC_REFERENCE_INT2560MV
+ #else
+ #define VTARGET_REF_MASK ADC_REFERENCE_AVCC