| Symptom | Likely Cause | Solution | |---------|--------------|----------| | LCD lights but shows dark boxes | Contrast too high or initialization failed | Edit JHD model properties; adjust the "Contrast" parameter to 30-50. | | No text, only blank | Wrong I2C address | Double-check address in code vs. model properties. Try 0x20, 0x27, 0x3F. | | Simulation hangs or runs slow | Missing pull-ups on SDA/SCL | Add 4.7kΩ resistors from SDA to 5V and SCL to 5V. | | Garbage characters | Incorrect I2C timing or 4-bit init sequence | Ensure LiquidCrystal_I2C library is correct. For PIC users, verify delay loops. | | "No model specified" error | Library not installed correctly | Reinstall the JHD-2x16-I2C library files. |
| Feature | Proteus Simulation | Real JHD-2x16-I2C Module | |---------|--------------------|---------------------------| | Timing | Ideal, no delays | Requires precise power-up delays (usually 100-250ms) | | Pull-ups | Sometimes optional | Always required (4.7kΩ) | | Contrast | Adjustable via property | Physical potentiometer on the back | | Backlight | Always simulated | Can be controlled via transistor or jumper | | I2C Speed | Up to 400kHz stable | Real devices may struggle at 400kHz on long wires | jhd-2x16-i2c proteus
