1c92945f59
Currently, several example dependencies rely on the fact that all registered components are added to the build, along with components specified in common requirements. This results in longer build times because even unused components must be built. Switch all examples to use idf_minimal_build to compile only the components actually required by the example. Signed-off-by: Frantisek Hrbata <frantisek.hrbata@espressif.com>
| Supported Targets | ESP32 | ESP32-C2 | ESP32-C3 | ESP32-C5 | ESP32-C6 | ESP32-C61 | ESP32-H2 | 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.