| Supported Targets | ESP32 | ESP32-C2 | ESP32-C3 | ESP32-C5 | ESP32-C6 | ESP32-C61 | ESP32-H2 | ESP32-H21 | ESP32-P4 | ESP32-S2 | ESP32-S3 |
|---|
LCD tjpgd example
(See the README.md file in the upper level 'examples' directory for more information about examples.)
Overview
This example shows how to decode a jpeg image and display it on an SPI-interfaced LCD, and rotates the image periodically.
If you want to adapt this example to another type of display or pinout, check lcd_tjpgd_example_main.c for comments with some implementation details.
How to Use Example
Hardware Required
- An ESP development board
- An SPI-interfaced LCD
- An USB cable for power supply and programming
Hardware Connection
The connection between ESP Board and the LCD is as follows:
ESP Board LCD Screen
+---------+ +---------------------------------+
| | | |
| 3V3 +--------------+ VCC +----------------------+ |
| | | | | |
| GND +--------------+ GND | | |
| | | | | |
| DATA0 +--------------+ MOSI | | |
| | | | | |
| PCLK +--------------+ SCK | | |
| | | | | |
| CS +--------------+ CS | | |
| | | | | |
| D/C +--------------+ D/C | | |
| | | | | |
| RST +--------------+ RST | | |
| | | | | |
|BK_LIGHT +--------------+ BCKL +----------------------+ |
| | | |
+---------+ +---------------------------------+
The GPIO number used by this example can be changed in lcd_tjpgd_example_main.c, where:
| GPIO number | LCD pin |
|---|---|
| EXAMPLE_PIN_NUM_PCLK | SCK |
| EXAMPLE_PIN_NUM_CS | CS |
| EXAMPLE_PIN_NUM_DC | DC |
| EXAMPLE_PIN_NUM_RST | RST |
| EXAMPLE_PIN_NUM_DATA0 | MOSI |
| EXAMPLE_PIN_NUM_BK_LIGHT | BCKL |
Especially, please pay attention to the level used to turn on the LCD backlight, some LCD module needs a low level to turn it on, while others take a high level. You can change the backlight level macro EXAMPLE_LCD_BK_LIGHT_ON_LEVEL in lcd_tjpgd_example_main.c.
Extra connections for 8-line LCD (Octal SPI)
Firstly, please run idf.py menuconfig and set the Drive a LCD with 8 data lines option at Example Configuration.
Change the extra GPOIs used by octal SPI in lcd_tjpgd_example_main.c, where:
| GPIO number | LCD pin |
|---|---|
| PIN_NUM_DATA1 | D1 |
| PIN_NUM_DATA2 | D2 |
| PIN_NUM_DATA3 | D3 |
| PIN_NUM_DATA4 | D4 |
| PIN_NUM_DATA5 | D5 |
| PIN_NUM_DATA6 | D6 |
| PIN_NUM_DATA7 | D7 |
Build and Flash
Run idf.py -p PORT flash monitor to build, flash and monitor the project. A flowing picture will be shown on the LCD screen.
(To exit the serial monitor, type Ctrl-].)
See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
Troubleshooting
For any technical queries, please open an [issue] (https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.