String constants must be enclosed in double quotation marks. E.g. "Hello world".
If you place a string between quotes as a function parameter, this string will automatically be considered as constant and will be placed in FLASH memory.
Example:
/ * this function displays a string located in SRAM */
void display_ram(char *s) {
/* ....... */
}
/ * this function displays a string located in FLASH */
void display_flash(char flash *s) {
/* ....... */
}
void main(void) {
/* this will not work !!! */
/* because the function addresses the string as */
/* it is located in SRAM, but the string "Hello world" */
/* is constant and is placed in FLASH */
display_ram("Hello world");
/* this will work !!! */
/* the function addresses the string as it is located in FLASH */