Lot of improvements on the road:

• Added HELP command to automatically list the line where a program error has occurred;
• added modulo operator '%' to make modulus operations between integers (returns the remainder of an integer division);
• added integer division operator '#' (return the integer part of a division);
• added support for function keys into firmware;
• added KEY command to manage function keys: it is now possible to print the current functions and assign new functions to the keys;
• revised PAUSE code: it is now possible to break the delay with the "RUN STOP" key;
• better error management when in graphic modes: now if an error occurs in G2 and G3 modes, the BASIC interpreter returns into G1 mode; same behavior if an error occurs in direct mode while in graphics modes;
• pressing the "RUN STOP" key in direct mode while in graphic modes leads the interpreter to return to G1 mode.

Grab the new ROM file here: https://github.com/leomil72/LM80C