The E1832 Display Switch Interface allows a microcontroller to write an LCD and read two keyswitches using only 5 I/O pins for menu navigation, user settings, or status updates. A fast serial to parallel shift register allows byte writes to an LCD. Operating voltage is from 2V to 6V and an on-board display contrast is included. Connectors include a 7 pin to the microcontroller and a standard 16 pin to the LCD. The module uses 3 microcontroller pins to write bytes to a standard 11 pin LCD interface. LCD instructions or data are sent serially as eight data bits plus the Register Select bit where they are converted to parallel format at the LCD connector. A single pulse on the LCD Enable completes the write.