Error Message "void ADCsync()' was declared 'extern' and later 'static' [-fpermi

Projects Programming
1

Could someone please take a look at the sketch I have attached?

When I try to compile I get the error in the subject.

It is written for the Zero or M0 Pro, and is a method for getting super fast A/D. I have been trying to figure out what the problem is for over a day now, but I am very new to arduino, and I just can't figure it out.

Kind regards
Bob.

adcdma.ino (3.79 KB)

2

Compiles without errors in 1.6.5 and latest 1.6.7 hourly build (Dec 4).

Fails in 1.6.6.
The IDE generates this prototype

void ADCsync();

which does not quite match the original

static __inline__ void ADCsync() __attribute__((always_inline, unused));
static void   ADCsync() {
  while (ADC->STATUS.bit.SYNCBUSY == 1); //Just wait till the ADC is free
}
3

I along with several others reported this bug in 1.6.6 a couple of weeks ago. The fix for 1.6.6 is to remove the word static from all function declarations but unless you need features of 1.6.6 I would revert to 1.6.5. You could always live dangerously and go for the daily pre-release build of 1.6.7 .