Changing the size of memory or changing the ROM version forces a reset of the PET.
The emulator has an IEEE-488 device at address 8. It can be used load and save (.prg) files.
Some programs don't run on ROM1 and some require more memory than the default 8K.
LETTER is a fun little diversion where you press a letter or number key, and the PET draws a large version of the corresponding character on the screen. This program does not store the pattern for each character, but instead constructs its display from a common library of individual components.