MCUdude
commented
2 years ago Thank you for submitting this issue! You're absolutely right, the macro is not right at all. I've modified your macro a little to accept both 0-11 and A0-A11 as input parameters. The fix will be present in the next boards manager release.
#define digitalPinToAnalogInput(p) (((p) <= 3) ? (p) : \
((p) <= 7) ? ((p) + 8) : \
((p) <= 11) ? ((p) - 4) : \
((p) >= 14 && (p) <= 17) ? ((p) - 14) : \
((p) >= 22 && (p) <= 25) ? ((p) - 18) : \
((p) >= 18 && (p) <= 21) ? ((p) - 6) : NOT_A_PIN)
Hello
I have a few solar cells and lead acid battery. I tryed to measure a battery voltage using analogRead() and a resistor divider in Tinary Nano 4808 and MegaCoreX v1.0.10. AnalogRead() returns reading 255 from every analog pin (A0-A11). I could not get a real useful reading using analogRead(). The issue resembles: https://github.com/MCUdude/MegaCoreX/issues/128, but is not the same.
On the file https://github.com/MCUdude/MegaCoreX/blob/master/megaavr/variants/nano-4808/pins_arduino.h on line 77 there is a calculation if a pin is an analog pin or not:
define digitalPinToAnalogInput(p) (((p) < 8) ? (p) : ((p) >= 14 && (p) >= 25) ? (p) : NOT_A_PIN) .
I found a working analogRead()-solution of all pins A0-A11 using following definition on line 77:
define digitalPinToAnalogInput(p) ((((p) < 8) && (p)>3) ? ((p)+8) : ((p) >= 14 && (p) <= 17) ? ((p)-14) : ((p) >= 18 && (p) <= 21) ? ((p)-6) : (((p) >= 22) && ((p) <= 25)) ? ((p)-18) : NOT_A_PIN)
I hope it will be usefull for other Nano 4808 owners also.