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WSAL10829 – 7inch HDMI LCD (B)/en

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Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

Summary

Technical overview of the Waveshare 7-inch HDMI LCD with a capacitive touch panel. The display supports use as a PC monitor and Raspberry Pi connection via HDMI and USB.

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Technical overview

  • Resolution: 800 × 480 pixels at a 60 Hz refresh rate.
  • 5-point capacitive touch panel over USB; under Windows the touch function is generally auto-detected.
  • Supported operating systems: Windows 7/8/8.1/10/11 as a monitor; Raspberry Pi OS, Ubuntu, Kali, and Retropie for Pi operation.
  • For Raspberry Pi use, the resolution must be set manually in /boot/config.txt, otherwise the display may behave abnormally.
  • EDID timing parameters: pixel clock 32 MHz, H addressable 800, H blanking 128, V addressable 480, V blanking 45, H front porch 40, H sync width 48, V front porch 13, V sync width 3.
  • Power draw: approximately 490 mA with the backlight on and about 90 mA with it off (5 V supply).
  • The backlight can be switched on or off using a switch on the rear of the unit.
  • To control the backlight via PWM, two resistors are replaced (R80 to 68 kΩ, R59 to 5.1 kΩ, R56 removed); the PWM pad connects to the Raspberry Pi P1 pin.

Commands and examples – verify before use:  

hdmi_group=2
hdmi_mode=87
hdmi_cvt 800 480 60 6 0 0 0
hdmi_drive=1
disable_splash=1
gpiodump | grep pwm
gpio -g mode 18 pwm
gpio pwmc 1000
gpio -g pwm 18 X   # X = 0–1024; 0 = brightest, 1024 = darkest

Notes and version constraints

  • The exact pin mapping for the PWM wiring depends on the diagram; verify the current hardware revision before soldering.
  • The command “gpiodump” is not present in the source text; only the gpio commands were documented.
  • When multiple monitors are connected simultaneously, configure this LCD as the primary display so the cursor can be controlled on it.
  • Some PCs detect HDMI devices only after a reboot; insufficient USB power can cause flickering – use an external 5V/2A supply via the DC connector if needed.
  • If thin red lines appear at the screen edge, add “hdmi_drive=1” to config.txt.
  • If the system does not auto-detect EDID, the listed timing parameters must be configured manually.

Source and revision record

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