Not everything needs ram you can perfectly write program having only few variables. Mostly what saw is exchange part of circuit to microcontroller which sometim

Not everything needs ram you can perfectly write program having only few variables. Mostly what saw is exchange part of circuit to microcontroller which sometimes led in saving big chunk of components, you can you mcu as simple state machine for specific task in circuit like power controller or sensor processing unit... For example I saw 3 mode led flashlights selling on ebay for 3$ have PIC12 (probably chinese clone).