首页
学习
活动
专区
圈层
工具
发布
    • 综合排序
    • 最热优先
    • 最新优先
    时间不限
  • 来自专栏嵌入式开发圈

    【12月】大彩串口屏RT-Thread Nano STM32表驱动法产品应用开发

    #define BACKLIGHT_LEVEL 3 #define BACKLIGHT_LEVEL_TEXT 5 BackLight_Handler backlight_handler ; , BACKLIGHT_LEVEL_TEXT, text_buf); AnimationPlayFrame (BACKLIGHT_PAGE, BACKLIGHT_LEVEL, level); } (backlight_handler.level--) : (backlight_handler.level = 0); Backlight_level_set(backlight_handler.level ); break ; case BACKLIGHT_ADD_BUTTON: (backlight_handler.level < 5) ? (backlight_handler.level++) : (backlight_handler.level = 5); Backlight_level_set(backlight_handler.level

    1.8K21发布于 2020-12-11
  • 来自专栏HackforFun

    U-Boot 驱动模型

    以 pwm backlight 为例: ? 通过 UBOOTDRIVER 的 id 可以看出,该设备(pwm backlight)驱动属于 UCLASSPANELBACKLIGHT 类。 ? 这里定义了 backlight 的 UCLASS_DRIVER。 该 uclass driver 提供了 backlight_enable(structudevice*dev) 和 backlight_set_brightness(structudevice*dev, #define backlight_get_ops(dev) ((struct backlight_ops *)(dev)->driver->ops) driver ? (UCLASS_PANEL_BACKLIGHT, dev, "backlight", &bldev); backlight_enable(bldev); backlight_set_brightness

    4.1K40发布于 2020-01-13
  • 来自专栏嵌入式开发圈

    基于瑞芯微RV1109 Linux屏幕背光调试心得

    (2)添加背光亮度分级表 在板厂端 dts 文件中定义背光亮度分级表: / { backlight: backlight { compatible = "pwm-backlight"; //这里配置使用哪路 /backlight/brightness [root@RV1126_RV1109:/]# echo 200 > /sys/class/backlight/backlight/brightness [root @RV1126_RV1109:/]# echo 255 > /sys/class/backlight/backlight/brightness [root@RV1126_RV1109:/]# echo 100 > /sys/class/backlight/backlight/brightness [root@RV1126_RV1109:/]# echo 180 > /sys/class/backlight /backlight/brightnessssss

    2.8K21发布于 2021-09-17
  • 来自专栏谭广健的专栏

    Android GPIO操作

    ); } public boolean gpio_input1(View v) { return RootCommand("echo 2 > /sys/class/backlight "); } public boolean gpio_input2(View v) { return RootCommand("echo 2 > /sys/class/backlight public boolean set_gpio0_high(View v) { //拉高 boolean FLAG = RootCommand("echo 1 > /sys/class/backlight (Exception e) { } } return true; } } 给模块上电命令: echo 1 > /sys/devices/backlight .26/backlight/rk28_bl/bp_powe 给模块下电命令: echo 0 > /sys/devices/backlight.26/backlight/rk28_bl/bp_powe 建议下电后

    2.8K31发布于 2020-07-06
  • 来自专栏智慧协同

    让Ubuntu“保存”屏幕亮度值解决每次开机亮度都最大的问题

    先查看一下你的屏幕亮度值的范围: sudo cat /sys/class/backlight/acpi_video0/max_brightness 到了ubuntu14.10后,路径就变为了 /sys/ class/backlight/intel_backlight/max_brightness.但改不改都没什么所谓了,因为14.10中 可以手动的调节光亮度,并且系统自动保存。 修改 /etc/rc.local , sudo vim /etc/rc.local 在最后的 exit 0 之前添加: echo 7 > /sys/class/backlight/acpi_video0

    2K50发布于 2019-06-13
  • 来自专栏嵌入式开发圈

    手把手之如何在嵌入式Linux上运行QT应用程序(以百问网imx6ull开发板为例)

    /bin/sh start() { echo 4 > /sys/class/backlight/backlight/brightness source /etc/profile 4、编写QT测试程序(二) 接下来我们来使用QT控件控制屏幕背光亮度,背光亮度的操作,只需要往下面这个文件里写具体范围的数值就可以控制背光亮度了: /sys/class/backlight/backlight ; } void MainWindow::on_horizontalSlider_valueChanged(int value) { qDebug() << value ; int backlight = value / 12; ui->label->setText(QString("backlight:%1").arg(backlight)); QString str = QString ("echo %1 > /sys/class/backlight/backlight/brightness").arg(backlight); QByteArray ba = str.toLatin1

    11.2K10发布于 2021-07-07
  • 来自专栏TencentOS-tiny

    STM32CubeMX |42-使用DMA2D加速显存数据传输

    . */ #define LCD_WIDTH 1024 #define LCD_HEIGHT 600 /** * @brief Backlight control pin * @param[in] brightness the value of lcd backlight. 首先是背光控制实现,应该使用pwm实现背光调节,本文中为了方便直接使用GPIO控制: void lcd_backlight_control(uint8_t bightness) { // todo : use pwm to control backlight if (bightness) { // turn on the backlight HAL_GPIO_WritePin (LCD_BL_GPIO_PORT, LCD_BL_GPIO_PIN, GPIO_PIN_SET); } else { // turn off the backlight

    4K30发布于 2021-07-23
  • 来自专栏linux驱动个人学习

    linux 设备驱动加载的先后顺序

    , ... }; LCD(xxx_lcd_device)设备先于PWM(xxxpwm_backlight_device)设备。 (记得PM操作 - resume/suspend的顺序 是和这个表的顺序保持一致的) 2.2 怀疑和编译顺序有关 Z:\kernel\drivers\video\Makefile:背光驱动(backlight /)的编译限于LCD驱动(xxxfb.o)的编译 obj-$(CONFIG_VT) += console/ obj-$(CONFIG_LOGO) += logo/ obj-y += backlight display/ ... obj-$(CONFIG_FB_xxx) += xxxfb.o ak_logo.o obj-$(CONFIG_FB_AK88) += ak88-fb/ obj-y += backlight 加载运行: xxxpwm_backlight_device的probe就会在xxx_lcd_device的probe之后执行,即LCD初始化先于PWM的初始化。

    4.6K40编辑于 2022-05-10
  • 来自专栏嵌入式开发板

    迅为国产RK3568开发板Android移植 LCD 屏幕

    共需要以下几个重点内容:dsi, route_dsi, backlight, vcc_lcd, dsi_in_vopb, dsi_in_vopl,vopb。 设备树 topeet_rk3568_lcds.dtsi 中添加如下图所示: 2.2 Backlight 背光常用的有三种情况: 一是 常开。 二是 背光 IC 使能后,输入 PWM 信号调光。 首先根据原理图,我们知道使用的是 pwm5, kernel/arch/arm64/boot/dts/rockchip/rk3568-evb.dtsi 文件里面 backlight1 节点如下所示: backlight1 : backlight1 { compatible = "pwm-backlight"; pwms = <&pwm5 0 25000 0>; brightness-levels = < 0 20 20 echo 100 > /sys/class/backlight/backlight/brightness

    4.3K61编辑于 2022-04-13
  • 来自专栏linux驱动个人学习

    高通移植mipi LCD的过程LK代码

    在msm_display_init()里先Turn on panel,再Turn on backlight; panel.power_func = mdss_dsi_panel_power; //turn on panel panel.bl_func = mdss_dsi_bl_enable; //turn on backlight 函数指向相应的函数中去; 2. 打开背光: /* Turn on backlight */ if (pdata->bl_func) ret = pdata->bl_func(1); 3. (enable); if (ret) dprintf(CRITICAL, "Backlight %s failed\n", enable ? : wled_backlight_ctrl; 7、更改LCD的参数: LCD的一些参数: VBPD(verticalback porch):表示在一帧图像开始时,垂直同步信号以后的无效的行数。

    1.9K20发布于 2018-07-30
  • 来自专栏韦东山嵌入式

    stm32mp157开发板LCD 显示测试&触摸屏测试

    先通过 cat 命令查看当前背光亮度等级: [root@100ask:~]# cat /sys/class/backlight/panel-backlight/brightness ? 最后设置背光亮度值为 1,可以看到 LCD 亮了: [root@100ask:~]# echo 0 > /sys/class/backlight/panel-backlight/brightness 参考资料

    2.6K41发布于 2020-10-15
  • 来自专栏全栈程序员必看

    允许Ubuntu14.04"保存"屏幕亮度值

    首先查看一下你的屏幕亮度值的范围: sudo cat /sys/class/backlight/acpi_video0/max_brightness 我的是15,也就是说亮度值能够在 0 ~ 15之间 改动 /etc/rc.local ,在最后的 exit 0 之前加入: echo 3 > /sys/class/backlight/acpi_video0/brightness 系统完毕启此举将最终运行脚本

    71510编辑于 2022-07-06
  • 来自专栏技术向

    捡垃圾系列-mpos机12864屏幕

    welding FPC 2 IC: ST7567, powerful function, good stability 3 Low power consumption: 1-100mW (not backlight is 0.3mW 3.3V, backlight is not more than 100mW) 4 Display content (1) 128*64 dot matrix monochrome the 12*12 dot matrix Chinese characters to calculate can display 10 words / *4 line. 5 Color: White backlight

    1.3K10发布于 2020-05-07
  • 技术分享 | i.MX8M Mini适配MIPI转eDP芯片

    clock-frequency = <27000000>; clock-output-names = "osc_27m"; }; lcd_backlight : lcd_backlight { compatible = "pwm-backlight"; pwms = <&pwm1 0 100000> panel { compatible = "test,test-edp-1080p"; //设置自己的屏幕匹配参数组 backlight = <&lcd_backlight>; no-hpd; port { panel1_in: endpoint

    63410编辑于 2024-05-08
  • 来自专栏瑞芯微

    【北京迅为】itop-3588开发板快速测试手册-银河麒麟系统功能测试

    输入以下命令查看当前屏幕背光值cat /sys/class/backlight/backlight/brightness输入以下命令设置背光熄灭echo 0 >/sys/class/backlight/ backlight/brightness输入以下命令设置背光亮起echo 200 >/sys/class/backlight/backlight/brightness4 按键测试首先给开发板上电,通过调试串口登录到开发板上

    71810编辑于 2024-09-09
  • 来自专栏AI算法能力提高班

    AIGC绘画图集 | 清爽风格

    quality, ((monochrome)), ((grayscale)), skin spots, acnes, skin blemishes, age spot, (outdoor:1.6), backlight quality, ((monochrome)), ((grayscale)), skin spots, acnes, skin blemishes, age spot, (outdoor:1.6), backlight quality, ((monochrome)), ((grayscale)), skin spots, acnes, skin blemishes, age spot, (outdoor:1.6), backlight quality, ((monochrome)), ((grayscale)), skin spots, acnes, skin blemishes, age spot, (outdoor:1.6), backlight

    1K10编辑于 2023-12-29
  • 来自专栏全志嵌入式那些事

    【吃灰开发板复活】DIY全志V3s随身终端屏幕适配,LVGL以及各种外设驱动移植教程

    compatible = "jianda,jd-t18003-t01"; reg = <0>; spi-max-frequency = <95000000>; backlight = <&panel_backlight>; dc-gpios = <&pio 4 9 0>; // PE9 reset-gpios = <&pio 4 8 0>; // PE8 rotation = <0>; }; }; 除spi外,需要添加一个背光节点,这样就可以在用户层操作背光: panel_backlight: panel-backlight { compatible = "gpio-backlight"; gpios = <&pio 4 7 GPIO_ACTIVE_HIGH>; // PE7

    1.9K10编辑于 2024-02-02
  • 来自专栏linux教程

    如何实现Linux系统光亮度自动调整

    输入命令: 复制代码 代码如下: cat /sys/class/backlight/acpi_video0/max_brightness 输出显示一个数字。比如小编的是15。如图。 注:如果是双显卡,则/sys/class/backlight/下还有video1和intel_backlight目录,各自里面都有max_brightness和actual_brightness,表示最大亮度和实际亮度 bin/sh #change brightness setting on startup or resume pkexec /usr/lib/gnome-settings-daemon/gsd-backlight-helper

    3K10编辑于 2023-04-25
  • 来自专栏码农爱学习的专栏

    【i.MX6ULL】驱动开发11——LCD驱动实践

    /* assigned backlight device */ /* set before framebuffer registration, remove after unregister */ struct backlight_device *bl_dev; /* Backlight level curve */ struct mutex bl_curve_mutex; u8 bl_curve[FB_BACKLIGHT_LEVELS]; #endif #ifdef CONFIG_FB_DEFERRED_IO struct delayed_work deferred_work 节点: backlight { compatible = "pwm-backlight"; pwms = <&pwm1 0 5000000>; brightness-levels /backlight/backlight 通过下面的指令可以实时修改屏幕的亮度,比如修改亮度为1: echo 1 > brightness 总结 本篇介绍了LCD屏幕驱动相关知识并进行了实验,因为

    2K30编辑于 2021-12-27
  • LCD 显示--lvds

    2.原理图 3.设备数添加 lvds0_panel { compatible = "boe,ev121wxm-n10-1850"; backlight = <&lvds_backlight endpoint { remote-endpoint = <&lvds_out>; }; }; }; lvds_backlight : lvds_backlight { compatible = "pwm-backlight"; pwms = <&pwm2 0 100000 0>; status

    13410编辑于 2026-02-02
领券