I currently have this Pro Mini code in a sketch: //global: char *menuText[] = { // pointers to Menu options (char*)"SET DATE/TIME", // set RTC date and time (char*)"SET CHKIN HOURS", // set one to three daily checkin hours (char*)"AUTO ADJUST DST"…

const type array[] PROGMEM = { "one", "two", "tre" }; I used "flat" arrays, so inside the braces, the commas go away, and it's just one long string, but my strings in one array were all the same length so I can calculate where I need to read. [image] LEDsequencer - Wokwi ESP32, STM32…

There are a couple of ways to do it. If all the char arrays are the same length, or nearly the same length, then a 2-dimensional array can be used: const char menuText[][17] PROGMEM = { // pointers to Menu options "SET DATE/TIME", // set RTC date and time "SET …

No, unfortunately that does not work. The array of char* would go into PROGMEM, but the char arrays would go into ram.

Ok, I understand. Thanks again.

Note that this does rely on the lcd library inheriting from print, which has an overload of the print() function that uses __FlashStringHelper* to signify that a char* points to PROGMEM instead of ram.

I don't know what that means. But if it compiles, does that mean the library does all that correctly?

Yes, if it compiles then the library has a function that takes the __FlashStringHelper*. All the lcd libraries I'm familiar with will work, but there is always the chance someone is using there own code or a more obscure library.

The problems of a non-Von Neumann architecture ...

[image] ShermanP: add PROGMEM to the array I had originally Too many dimensions cause pointer/reference issues. That is why I (in my link) removed all the commas after the quotes to make the data one-dimension. Only needed a little row/col math to get the right data.

Help with PROGMEM and char arrays

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ShermanP February 8, 2026, 2:18am 4

Thanks very much. But each string has to have it's own PROGMEM? I couldn't just add PROGMEM to the array I had originally, with the (char*) things?

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Help with PROGMEM and char arrays

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