lcd.setCursor(0, 1); lcd.print("Proteus Sim OK");
Ensure the PCF8574 address pins (A0, A1, A2) are grounded to maintain the address in simulation. Library Configuration Do not use the standard LiquidCrystal_I2C
A standard 16x2 LCD (like the LM016L) uses an HD44780 controller requiring a 4-bit or 8-bit parallel interface. This consumes D4-D7, RS, RW, and E pins.
: The "I2C" part of the model refers to an onboard PCF8574 I/O expander . This chip converts the serial data from the I2C bus into the parallel signals needed by the LCD, significantly simplifying circuit design.
For the JHD-2X16-I2C specifically, standard LiquidCrystal libraries might fail due to controller differences.