As part of a bigger project, I want to save my programs' general output strings to a text file on the SD card instead of sending it down Serial all the time. Doing this is straightforward:
#include <SPI.h> // for SD storage
#include <SD.h> // for SD storage
void addToBlackBox(char* in)
blackBox = SD.open("BB.TXT", FILE_WRITE);
This function works for well enough, but I need to save memory because of my elaborate program. The idea that seemed the simplest was to put all the non-changing strings I wanted on the SD card in F(), the flash memory. So I tried this:
, but the compiler complained about my parameter type in addToBlackBox(), claiming that it should be a const_FlashStringHelper* . So I changed it to that in the parameters, but then the compiler complained even more, claiming that "variable or field 'addToBlackBox' declared void". I tried poking around the class files of classes that had built-in print()s and println()s, but I couldn't really find out why println() doesn't care about whether it's arguments are in F() or not. Googling it didn't help much either, since I could find little documentation on F() itself.
Please share some experience. Maybe I should approach the entire situation differently? How can I allow addToBlackBox() to accept its' argument from the flash memory?
PS I'm using a Seeeduino Stalker V2.3, and I got my libraries for SD from here: https://code.google.com/p/sdfatlib/downloads/detail?name=sdfatlib20130313.zip&can=2&q=