Overlay LCD TFT 3.2 inch HY32D make it works on Beagle Bone Black

Question

I am looking for some help to make works the LCD HY32D on the Beagle Bone Black.

I have connected this LCD called HY32D on the following PIN of the BBB:

    "P8.45",    // lcd: lcd_data0 
    "P8.46",    // lcd: lcd_data1 
    "P8.43",    // lcd: lcd_data2 
    "P8.44",    // lcd: lcd_data3 
    "P8.41",    // lcd: lcd_data4 
    "P8.42",    // lcd: lcd_data5 
    "P8.39",    // lcd: lcd_data6 
    "P8.40",    // lcd: lcd_data7 
    "P8.37",    // lcd: lcd_data8 
    "P8.38",    // lcd: lcd_data9 
    "P8.36",    // lcd: lcd_data10 
    "P8.34",    // lcd: lcd_data11 
    "P8.35",    // lcd: lcd_data12 
    "P8.33",    // lcd: lcd_data13 
    "P8.31",    // lcd: lcd_data14 
    "P8.32",    // lcd: lcd_data15 

    "P9.12",    // lcd RS: gpio1_28 
    "P9.42A",   // lcd RD: gpio0_7 
    "P8.14",    // lcd WR: gpio0_26
    "P8.16",    // lcd RESET: gpio1_14

Then I found an overlay called cape-bone-lcd3-00A0.dts and I did try to edit it to adapt to the LCD HY32D,

here the modified dts: http://support.rfberrypi.com/download/BB-LCD-HY32D-00A0.dts

but I do not have much experience in writing an overlay and a part that my main question is how can I redirect the video output to this overlay?

RFberryPi RFberryPi · Accepted Answer · 2015-07-22T14:34:38

I have solved my problem about driver for the LCD. First I have wrote the overlay:

/dts-v1/;
/plugin/;

/{
       compatible = "ti,beaglebone", "ti,beaglebone-black";
       part-number = "lcd_my_try";
       version = "00A0";

       fragment@0 {
             target = <&am33xx_pinmux>;

             __overlay__ {
                  pinctrl_test: lcd_my_try_Pins {
            pinctrl-single,pins = <

                    0xa0 0x2f   /* lcd_data0.lcd_data0, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xa4 0x2f   /* lcd_data1.lcd_data1, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xa8 0x2f   /* lcd_data2.lcd_data2, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xac 0x2f   /* lcd_data3.lcd_data3, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xb0 0x2f   /* lcd_data4.lcd_data4, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xb4 0x2f   /* lcd_data5.lcd_data5, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xb8 0x2f   /* lcd_data6.lcd_data6, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xbc 0x2f   /* lcd_data7.lcd_data7, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xc0 0x2f   /* lcd_data8.lcd_data8, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xc4 0x2f   /* lcd_data9.lcd_data9, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xc8 0x2f   /* lcd_data10.lcd_data10, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xcc 0x2f   /* lcd_data11.lcd_data11, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xd0 0x2f   /* lcd_data12.lcd_data12, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xd4 0x2f   /* lcd_data13.lcd_data13, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xd8 0x2f   /* lcd_data14.lcd_data14, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */
                    0xdc 0x2f   /* lcd_data15.lcd_data15, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT | AM33XX_PULL_DISA */

                    0x78 0x2f   // lcd_rs.lcd_rs, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT 
                    0x164 0x2f  // lcd_rd.lcd_rd, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT 
                    0x28 0x2f   // lcd_wr.lcd_wr, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT 
                    0x38 0x2f   // lcd_reset.lcd_reset, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT 
                    0x30 0x2f   // lcd_cs.lcd_cs, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT 

                    0xec 0x07   // lcd_ac_bias_en.gpio2_25 OMAP_MUX_MODE7 | AM33XX_PIN_OUTPUT 

                    //touch panel ADS7843 = XPT2046
                    0x34 0x2f   // touch_cs.gpio1_13, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT (chip select)
                    0x7c 0x2f   // touch_sck.gpio1_29, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT (clock)
                    0x3c 0x2f   // touch_si.gpio1_15, OMAP_MUX_MODE0 | AM33XX_PIN_OUTPUT (serial data in)

                    0x8c 0x2f   // touch_irq.gpio2_1, OMAP_MUX_MODE0 | AM33XX_PIN_INPUT (interrupt on touch)
                    0x2c 0x2f   // touch_so.gpio0_27, OMAP_MUX_MODE0 | AM33XX_PIN_INPUT (serial data output)


            >;
          };
             };
       };

       fragment@1 {
        target = <&ocp>;
        __overlay__ {
            test_helper: helper {
                compatible = "bone-pinmux-helper";
                pinctrl-names = "default";
                pinctrl-0 = <&pinctrl_test>;
                status = "okay";
            };
        };
    };
};

I named it as :

lcd_my_try.dts

I have compiled it on the BBB with this command:

dtc -O dtb -o lcd_my_try-00A0.dtbo -b 0 -@ lcd_my_try.dts

Then I loaded it:

cp lcd_my_try-00A0.dtbo /lib/firmware echo lcd_my_try > /sys/devices/bone_capemgr*/slots

I have loaded the name of the GPIO used with a bash file with the following contents:

#!/bin/bash

echo "Loading GPIO into /sys/class/gpio/export"

echo "Setting UP LCD_DATA_0"
echo 70 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio70/direction

echo "Setting UP LCD_DATA_1"
echo 71 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio71/direction

echo "Setting UP LCD_DATA_2"
echo 72 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio72/direction

echo "Setting UP LCD_DATA_3"
echo 73 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio73/direction

echo "Setting UP LCD_DATA_4"
echo 74 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio74/direction

echo "Setting UP LCD_DATA_5"
echo 75 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio75/direction

echo "Setting UP LCD_DATA_6"
echo 76 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio76/direction

echo "Setting UP LCD_DATA_7"
echo 77 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio77/direction

echo "Setting UP LCD_DATA_8"
echo 78 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio78/direction

echo "Setting UP LCD_DATA_9"
echo 79 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio79/direction

echo "Setting UP LCD_DATA_10"
echo 80 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio80/direction

echo "Setting UP LCD_DATA_11"
echo 81 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio81/direction

echo "Setting UP LCD_DATA_12"
echo 8 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio8/direction

echo "Setting UP LCD_DATA_13"
echo 9 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio9/direction

echo "Setting UP LCD_DATA_14"
echo 10 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio10/direction

echo "Setting UP LCD_DATA_15"
echo 11 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio11/direction

echo "Setting UP LCD_RS"
echo 60 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio60/direction

echo "Setting UP LCD_RD"
echo 7 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio7/direction

echo "Setting UP LCD_WR"
echo 26 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio26/direction

echo "Setting UP LCD_RESET"
echo 46 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio46/direction

echo "Setting UP LCD_CS"
echo 44 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio44/direction

echo "Setting UP LCD_BLVDD"
echo 89 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio89/direction

echo "----TOUCH PANEL----"
echo "Setting UP TOUCH_CS"
echo 45 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio45/direction

echo "Setting UP TOUCH_SCK"
echo 61 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio61/direction

echo "Setting UP TOUCH_SI"
echo 47 > /sys/class/gpio/export
echo "out" > /sys/devices/virtual/gpio/gpio47/direction

echo "Setting UP TOUCH_IRQ"
echo 65 > /sys/class/gpio/export
echo "in" > /sys/devices/virtual/gpio/gpio65/direction

echo "Setting UP TOUCH_SO"
echo 27 > /sys/class/gpio/export
echo "in" > /sys/devices/virtual/gpio/gpio27/direction

Finally I was ready to write on the LCD!

Overlay LCD TFT 3.2 inch HY32D make it works on Beagle Bone Black

1 Answers