ViewSonic LS831WU Control Spec

Summary

Laser phosphor projector with RS-232C control interface. Supports power control, source routing, image adjustment, and display settings via hexadecimal command packets. Serial config: 19200 baud/8-N-1 by default.

Transport

protocols:
  - serial
serial:
  baud_rate: 19200  # default; supports 4800/9600/19200/38400
  data_bits: 8
  parity: none
  stop_bits: 1
  flow_control: none
auth:
  type: none  # inferred: no auth procedure in source

Traits

- powerable       # power ON/OFF commands present
- routable        # source input switching present
- queryable       # read commands returning state present
- levelable       # contrast, brightness, sharpness, zoom, focus, volume, white balance present

Actions

- id: power_on
  label: Power On
  kind: action
  params: []

- id: power_off
  label: Power Off
  kind: action
  params: []

- id: quick_power_off
  label: Quick Power Off
  kind: action
  params: []

- id: quick_power_on
  label: Quick Power On
  kind: action
  params: []

- id: splash_screen
  label: Splash Screen
  kind: action
  params:
    - name: mode
      type: enum
      values: [black, blue]

- id: high_altitude_mode
  label: High Altitude Mode
  kind: action
  params:
    - name: mode
      type: enum
      values: [off, on, auto]

- id: lamp_mode
  label: Lamp Mode
  kind: action
  params:
    - name: mode
      type: enum
      values: [normal, full_normal, eco, eco_extended]

- id: presentation_timer
  label: Presentation Timer
  kind: action
  params:
    - name: timer
      type: enum
      values: [off, timer_1, timer_2, timer_3]

- id: contrast
  label: Contrast
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: brightness
  label: Brightness
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: white_balance_red_gain
  label: White Balance Red Gain
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: white_balance_green_gain
  label: White Balance Green Gain
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: white_balance_blue_gain
  label: White Balance Blue Gain
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: sharpness
  label: Sharpness
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: zoom
  label: Zoom
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: focus
  label: Focus
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: freeze
  label: Freeze
  kind: action
  params:
    - name: state
      type: enum
      values: [on, off]

- id: aspect_ratio
  label: Aspect Ratio
  kind: action
  params:
    - name: ratio
      type: enum
      values: [auto, 4_3, 16_9, 16_10, panorama, 2_35_1, 2_35_2, native]

- id: source_input
  label: Source Input
  kind: action
  params:
    - name: input
      type: enum
      values: [d_sub_comp1, hdmi1, hdmi2, hdbaset, usb_reader_usb1, lan_wifi_display, usb_display]

- id: quick_auto_search
  label: Quick Auto Search
  kind: action
  params:
    - name: state
      type: enum
      values: [on, off]

- id: mute
  label: Mute
  kind: action
  params:
    - name: state
      type: enum
      values: [on, off]

- id: volume
  label: Volume
  kind: action
  params:
    - name: direction
      type: enum
      values: [increase, decrease]

- id: volume_set
  label: Volume Set
  kind: action
  params:
    - name: value
      type: integer
      description: Volume value

- id: dde_mode
  label: DDE Mode
  kind: action
  params:
    - name: mode
      type: enum
      values: [film, video, standard]

- id: color_temperature
  label: Color Temperature
  kind: action
  params:
    - name: temperature
      type: enum
      values: [6500k, 7000k, 7500k, 9000k, 9300k, user1, user2, user3, user4]

- id: color_space
  label: Color Space
  kind: action
  params:
    - name: space
      type: enum
      values: [auto, rgb, yuv]

- id: input_skip
  label: Input Skip
  kind: action
  params:
    - name: input_index
      type: integer
      description: Input index (0-based)
    - name: state
      type: enum
      values: [on, off]
- id: reset_to_factory_default
  label: Reset To Factory Default
  kind: action
  params: []

- id: lan_reset
  label: LAN Reset
  kind: action
  params: []

Feedbacks

- id: power_status
  label: Power Status
  type: enum
  values:
    - on
    - warm_up
    - cool_down
    - off

- id: splash_screen_status
  label: Splash Screen Status
  type: enum
  values: [black, blue]

- id: quick_power_off_status
  label: Quick Power Off Status
  type: enum
  values: [off, on]

- id: high_altitude_mode_status
  label: High Altitude Mode Status
  type: enum
  values: [off, on, auto]

- id: lamp_mode_status
  label: Lamp Mode Status
  type: enum
  values: [normal, full_normal, eco, eco_extended]

- id: presentation_timer_status
  label: Presentation Timer Status
  type: enum
  values: [off, timer_1, timer_2, timer_3]

- id: contrast_status
  label: Contrast Status
  type: enum
  values: [increase, decrease]

- id: brightness_status
  label: Brightness Status
  type: enum
  values: [increase, decrease]

- id: white_balance_red_gain_status
  label: White Balance Red Gain Status
  type: enum
  values: [increase, decrease]

- id: white_balance_green_gain_status
  label: White Balance Green Gain Status
  type: enum
  values: [increase, decrease]

- id: white_balance_blue_gain_status
  label: White Balance Blue Gain Status
  type: enum
  values: [increase, decrease]

- id: sharpness_status
  label: Sharpness Status
  type: enum
  values: [increase, decrease]

- id: zoom_status
  label: Zoom Status
  type: enum
  values: [increase, decrease]

- id: focus_status
  label: Focus Status
  type: enum
  values: [increase, decrease]

- id: freeze_status
  label: Freeze Status
  type: enum
  values: [on, off]
  notes: Uses 1-byte value mapping per table 3.2.1

- id: aspect_ratio_status
  label: Aspect Ratio Status
  type: enum
  values: [auto, 4_3, 16_9, 16_10, panorama, 2_35_1, 2_35_2, native]

- id: source_input_status
  label: Source Input Status
  type: enum
  values: [d_sub_comp1, hdmi1, hdmi2, hdbaset, usb_reader_usb1, lan_wifi_display, usb_display]

- id: quick_auto_search_status
  label: Quick Auto Search Status
  type: enum
  values: [on, off]

- id: mute_status
  label: Mute Status
  type: enum
  values: [on, off]

- id: volume_status
  label: Volume Status
  type: enum
  values: [increase, decrease]

- id: dde_mode_status
  label: DDE Mode Status
  type: enum
  values: [film, video, standard]

- id: color_temperature_status
  label: Color Temperature Status
  type: enum
  values: [6500k, 7000k, 7500k, 9000k, 9300k, user1, user2, user3, user4]

- id: color_space_status
  label: Color Space Status
  type: enum
  values: [auto, rgb, yuv]

- id: input_skip_status
  label: Input Skip Status
  type: enum
  values: [on, off]

- id: temperature
  label: Temperature
  type: integer
  description: Operating temperature in degrees Celsius (Byte7~Byte10 hex conversion)

- id: light_source_usage_time
  label: Light Source Usage Time
  type: integer
  description: Hours (Byte7~Byte10 hex conversion)

Variables

# UNRESOLVED: volume write value range not specified in source

Events

# UNRESOLVED: no unsolicited event notifications described in source

Macros

# UNRESOLVED: no multi-step macro sequences described in source

Safety

confirmation_required_for: []
interlocks:
  - Do not send commands during Warm Up state (initial HW/FW setup)
  - Do not send commands during Cool Down state (HW/FW closing sequence)
  - Mute function only active when input source is applied
  - Auto Adjust function only active for non-digital inputs (VGA/Computer1/D-sub)
  - After Reset to Factory Default, user must reboot projector to clear parameters
  - Power Off requires LAN control setting to be ON for LAN reboot

Notes

• Serial connector: DSUB 9-pin male (outside view). Only 3 pins needed for control: RXD (pin2), TXD (pin3), GND (pin5). Crossover (null modem) cable may be required.
• Default baud rate: 19200 bps. Supported rates: 4800/9600/19200/38400.
• Command packet format: control unit sends command followed by checksum. Projector always responds.
• LAN control uses same code format with "0x" replaced by "" via port 4661. Exception: Pro9 series uses port 23.
• Response formats: 1-byte and 2-byte response packets documented.
• Error response status available for service debug (32 bytes total).
• When first response byte is 0x00, function is disabled (greyed out in OSD).
• HDMI Range: Enhanced/Full = 0–255 steps; Normal/Limited = 16–235 steps.
• Factory Reset commands (Reset to Factory Default, LAN Reset) require reboot to clear parameters.

Provenance

source_domains:
  - viewsonicglobal.com
  - viewsonicvsa.freshdesk.com
source_urls:
  - "https://www.viewsonicglobal.com/public/products_download/user_guide/projector/LSC_6_7_8_Series/LSC%20Series%20RS-232%20LAN%20Control%20Protocol%20Specification.pdf"
  - https://viewsonicvsa.freshdesk.com/support/solutions/articles/43000470420-viewsonic-projector-rs232-protocol
  - "https://www.viewsonicglobal.com/public/products_download/user_guide/projector/LS950WU_LS951WU_LS960WU/RS-232%20LAN%20Control%20Protocol%20Specification%20V1.5.pdf"
  - https://www.viewsonicglobal.com/public/products_download/software/projector/ls/ViewSonic_projector_LS831WU_Serial.zip
retrieved_at: 2026-05-22T00:43:58.281Z
last_checked_at: 2026-06-10T01:30:52.637Z

Verification Summary

verdict: verified
checked_at: 2026-06-10T01:30:52.637Z
matched_actions: 29
action_count: 29
confidence: medium
summary: "All 29 spec actions matched source commands; full command coverage at spec's granularity; all transport parameters verified. (7 unresolved item(s) noted in Known Gaps.)"

Known Gaps

- "LAN control port (4661 mentioned) not fully documented in serial spec section"
- "volume write value range not specified in source"
- "no unsolicited event notifications described in source"
- "no multi-step macro sequences described in source"
- "LAN control detailed command set not included in this serial protocol document"
- "volume write value range (0–?) not stated in source"
- "firmware version compatibility not stated in source"

From the AI4AV catalog (https://ai4av.net) · ODbL-1.0