Summary

The Shure P4800 is a 4-input, 8-output matrix mixer / system processor controlled over a 7-wire RS-232 interface using SysEx-style messages wrapped in F0h..F7h. Device ID is set via DIP switches (0 to 15). This spec covers preset recall, per-input and per-output settings (mute, polarity, +4/-10 scaling, pad, volume), matrix mixpoint settings, and full state queries.

Transport

protocols:
  - serial
serial:
  baud_rate: 19200
  data_bits: 8
  parity: none
  stop_bits: 1
  flow_control: none
auth:
  type: UNRESOLVED  # source does not explicitly state an authentication procedure or its absence

Cable note (from source): P4800 uses a 7-wire RS-232 port. Crestron/AMX controllers use 5-wire. A custom cable is required. The P4800 requires 5-12 V on the DTR line; a 1 kOhm resistor is needed for a 5 V supply. All other wires pass straight through.

Traits

# - routable        inferred: matrix mixpoint activate/deactivate commands present
# - levelable       inferred: per-input, per-output, and per-mixpoint volume control present
# - queryable       inferred: query commands for every setting present

Actions

# SysEx frame format (set commands):
#   F0h 00h 01h 00h <Device ID> 0Ah 69h <function> 00h <ID> <VA> F7h
#
# <Device ID>: 00h-0Fh, must match the DIP switch setting on the back of the P4800.
# After every set command, the P4800 echoes the command and then sends a return string.
# The 4th byte position (channel nibble) is 00h in all source examples.
#
# Volume-control formulas (from source):
#   For input/output per-channel volume:
#     <VA> = [2 * (Control Setting)] & 7Fh
#     Control Setting range: -30 to +30 (1 unit = 1 dB).
#   For mixpoint / mixer-output volume:
#     <VA> = (Control Setting) & 7Fh
#     Control Setting range: 0 to 127
#       0       = -Infinity
#       1-26    = -105 to -42.5 dB in 2.5 dB steps
#       27-127  = -40.0 to +10.0 dB in 0.5 dB steps
#   For relative (+/-) dB changes:
#     <VA> = [2 * (dB Change)] & 7Fh
#     Example: decrease by 2 dB => <VA> = 7Ch.

# --- Preset recall (short-frame, not SysEx) ---
- id: change_preset
  label: Change Preset
  kind: action
  command: "C{device_id}{preset}"  # short frame: C <n> h <pp> h
  params:
    - name: device_id
      type: integer
      description: Device ID (0-15) set by DIP switches; encoded as the low nibble of the first byte (high nibble = Ch).
    - name: preset
      type: integer
      description: Preset number minus 1. Range 0 to 127 (i.e. presets 1 to 128).

# --- Inputs: Mute ---
- id: input_toggle_mute
  label: Input Toggle Mute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 00 {input_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15 (DIP switch).
    - name: input_id
      type: integer
      description: Input channel ID byte: 04h=Input 1, 05h=Input 2, 06h=Input 3, 07h=Input 4.
- id: input_force_mute
  label: Input Force Mute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {input_id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 04h=Input 1, 05h=Input 2, 06h=Input 3, 07h=Input 4.
- id: input_force_unmute
  label: Input Force Unmute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {input_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 04h=Input 1, 05h=Input 2, 06h=Input 3, 07h=Input 4.

# --- Inputs: Polarity ---
- id: input_toggle_polarity
  label: Input Toggle Polarity
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 00 {input_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 08h=Input 1, 09h=Input 2, 0Ah=Input 3, 0Bh=Input 4.
- id: input_force_polarity_positive
  label: Input Force Polarity (+)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {input_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 08h=Input 1, 09h=Input 2, 0Ah=Input 3, 0Bh=Input 4.
- id: input_force_polarity_negative
  label: Input Force Polarity (-)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {input_id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 08h=Input 1, 09h=Input 2, 0Ah=Input 3, 0Bh=Input 4.

# --- Inputs: +4/-10 scaling ---
- id: input_toggle_scaling
  label: Input Toggle Scaling
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 00 {input_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 0Ch=Input 1, 0Dh=Input 2, 0Eh=Input 3, 0Fh=Input 4.
- id: input_force_scaling_plus4
  label: Input Force +4 dBu Scaling
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {input_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 0Ch=Input 1, 0Dh=Input 2, 0Eh=Input 3, 0Fh=Input 4.
- id: input_force_scaling_minus10
  label: Input Force -10 dBV Scaling
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {input_id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 0Ch=Input 1, 0Dh=Input 2, 0Eh=Input 3, 0Fh=Input 4.

# --- Inputs: Volume (set absolute) ---
- id: input_set_volume
  label: Input Set Volume
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 00 00 {input_id} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 00h=Input 1, 01h=Input 2, 02h=Input 3, 03h=Input 4.
    - name: va
      type: integer
      description: "<VA> = [2 * ControlSetting] AND 7Fh. ControlSetting range -30 to +30 (1 step = 1 dB)."

# --- Inputs: Volume (relative +/-) ---
- id: input_change_volume
  label: Input Change Volume (relative dB)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 04 00 {input_id} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input channel ID byte: 00h=Input 1, 01h=Input 2, 02h=Input 3, 03h=Input 4.
    - name: va
      type: integer
      description: "<VA> = [2 * dBChange] AND 7Fh. Example: -2 dB => <VA> = 7Ch."

# --- Outputs: Mute ---
- id: output_toggle_mute
  label: Output Toggle Mute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output channel ID byte: 46h=Out 1, 47h=Out 2, 48h=Out 3, 49h=Out 4, 4Ah=Out 5, 4Bh=Out 6, 4Ch=Out 7, 4Dh=Out 8.
- id: output_force_mute
  label: Output Force Mute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output channel ID byte: 46h=Out 1 .. 4Dh=Out 8.
- id: output_force_unmute
  label: Output Force Unmute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output channel ID byte: 46h=Out 1 .. 4Dh=Out 8.

# --- Outputs: Polarity ---
# Source ambiguity: set-command polarity section uses 55h for both Output 7 and Output 8;
# the query section uses 54h for Output 7 and 55h for Output 8. Set commands are transcribed
# verbatim from the source per the documented ambiguity.
- id: output_toggle_polarity
  label: Output Toggle Polarity
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output polarity ID byte: 4Eh=Out 1, 4Fh=Out 2, 50h=Out 3, 51h=Out 4, 52h=Out 5, 53h=Out 6, 55h=Out 7, 55h=Out 8. UNRESOLVED: source lists 55h for both Out 7 and Out 8; the query section uses 54h for Out 7.
- id: output_force_polarity_positive
  label: Output Force Polarity (+)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output polarity ID byte: 4Eh=Out 1, 4Fh=Out 2, 50h=Out 3, 51h=Out 4, 52h=Out 5, 53h=Out 6, 55h=Out 7, 55h=Out 8. UNRESOLVED: source lists 55h for both Out 7 and Out 8; the query section uses 54h for Out 7.
- id: output_force_polarity_negative
  label: Output Force Polarity (-)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output polarity ID byte: 4Eh=Out 1, 4Fh=Out 2, 50h=Out 3, 51h=Out 4, 52h=Out 5, 53h=Out 6, 55h=Out 7, 55h=Out 8. UNRESOLVED: source lists 55h for both Out 7 and Out 8; the query section uses 54h for Out 7.

# --- Outputs: +4/-10 scaling ---
- id: output_toggle_scaling
  label: Output Toggle Scaling
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output scaling ID byte: 56h=Out 1, 57h=Out 2, 58h=Out 3, 59h=Out 4, 5Ah=Out 5, 5Bh=Out 6, 5Ch=Out 7, 5Dh=Out 8.
- id: output_force_scaling_plus4
  label: Output Force +4 dBu Scaling
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output scaling ID byte: 56h=Out 1 .. 5Dh=Out 8.
- id: output_force_scaling_minus10
  label: Output Force -10 dBV Scaling
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output scaling ID byte: 56h=Out 1 .. 5Dh=Out 8.

# --- Outputs: 20 dB Pad ---
- id: output_toggle_pad
  label: Output Toggle Pad (20 dB)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output pad ID byte: 5Eh=Out 1, 5Fh=Out 2, 60h=Out 3, 61h=Out 4, 62h=Out 5, 63h=Out 6, 64h=Out 7, 65h=Out 8.
- id: output_force_pad_off
  label: Output Force Pad Off
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output pad ID byte: 5Eh=Out 1 .. 65h=Out 8.
- id: output_force_pad_on
  label: Output Force Pad On
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 03 {output_id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output pad ID byte: 5Eh=Out 1 .. 65h=Out 8.

# --- Outputs: Volume (set absolute) ---
- id: output_set_volume
  label: Output Set Volume
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 00 03 {output_id} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output volume ID byte: 3Eh=Out 1, 3Fh=Out 2, 40h=Out 3, 41h=Out 4, 42h=Out 5, 43h=Out 6, 44h=Out 7, 45h=Out 8.
    - name: va
      type: integer
      description: "<VA> = [2 * ControlSetting] AND 7Fh. ControlSetting range -30 to +30 (1 step = 1 dB)."

# --- Outputs: Volume (relative +/-) ---
- id: output_change_volume
  label: Output Change Volume (relative dB)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 04 03 {output_id} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output volume ID byte: 3Eh=Out 1 .. 45h=Out 8.
    - name: va
      type: integer
      description: "<VA> = [2 * dBChange] AND 7Fh. Example: -2 dB => <VA> = 7Ch."

# --- Matrix Mixer: Mute Mixpoint ---
- id: mixpoint_toggle_mute
  label: Mixpoint Toggle Mute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 00 {id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = NMIXPOINTS + 15 + (Mix Point #). NMIXPOINTS = 4 * NOUTPUTS (32 for 4x8)."
- id: mixpoint_force_mute
  label: Mixpoint Force Mute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = NMIXPOINTS + 15 + (Mix Point #)."
- id: mixpoint_force_unmute
  label: Mixpoint Force Unmute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = NMIXPOINTS + 15 + (Mix Point #)."

# --- Matrix Mixer: Mute Mixer Output ---
# Source explicitly flags Toggle Mute (Mixer Output) as BUG - DOES NOT WORK.
- id: mixer_output_toggle_mute
  label: Mixer Output Toggle Mute (BUG: does not work)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 {idmsb} {idlsb} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) AND 7Fh."
- id: mixer_output_force_mute
  label: Mixer Output Force Mute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 {idmsb} {idlsb} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) AND 7Fh."
- id: mixer_output_force_unmute
  label: Mixer Output Force Unmute
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 {idmsb} {idlsb} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) AND 7Fh."

# --- Matrix Mixer: Polarity Mixpoint ---
- id: mixpoint_toggle_polarity
  label: Mixpoint Toggle Polarity
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 00 {id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = (2 * NMIXPOINTS) + 15 + (Mix Point #)."
- id: mixpoint_force_polarity_positive
  label: Mixpoint Force Polarity (+)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {id} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = (2 * NMIXPOINTS) + 15 + (Mix Point #)."
- id: mixpoint_force_polarity_negative
  label: Mixpoint Force Polarity (-)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 00 {id} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = (2 * NMIXPOINTS) + 15 + (Mix Point #)."

# --- Matrix Mixer: Polarity Mixer Output ---
# Source explicitly flags Toggle Polarity (Mixer Output) as BUG - DOES NOT WORK.
- id: mixer_output_toggle_polarity
  label: Mixer Output Toggle Polarity (BUG: does not work)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 {idmsb} {idlsb} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) AND 7Fh."
- id: mixer_output_force_polarity_positive
  label: Mixer Output Force Polarity (+)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 {idmsb} {idlsb} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) AND 7Fh."
- id: mixer_output_force_polarity_negative
  label: Mixer Output Force Polarity (-)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 {idmsb} {idlsb} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) AND 7Fh."

# --- Matrix Mixer: Volume Mixpoint ---
- id: mixpoint_set_volume
  label: Mixpoint Set Volume
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 00 00 {id} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = (Mix Point #) + 15."
    - name: va
      type: integer
      description: "<VA> = ControlSetting AND 7Fh. Range 0-127: 0=-Inf, 1-26=-105 to -42.5 dB in 2.5 dB steps, 27-127=-40.0 to +10.0 dB in 0.5 dB steps."
- id: mixpoint_change_volume
  label: Mixpoint Change Volume (relative dB)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 05 00 {id} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = (Mix Point #) + 15."
    - name: va
      type: integer
      description: "<VA> = [2 * dBChange] AND 7Fh."

# --- Matrix Mixer: Volume Mixer Output ---
# Source flags Increase/Decrease Volume (Mixer Output) as BUG - DOES NOT WORK.
- id: mixer_output_set_volume
  label: Mixer Output Set Volume
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 00 {idmsb} {idlsb} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + 15 + (NOutput #)) AND 7Fh."
    - name: va
      type: integer
      description: "<VA> = ControlSetting AND 7Fh. Range 0-127: 0=-Inf, 1-26=-105 to -42.5 dB in 2.5 dB steps, 27-127=-40.0 to +10.0 dB in 0.5 dB steps."
- id: mixer_output_change_volume
  label: Mixer Output Change Volume (BUG: does not work)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 05 {idmsb} {idlsb} {va} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + 15 + (NOutput #)) AND 7Fh."
    - name: va
      type: integer
      description: "<VA> = [2 * dBChange] AND 7Fh."

# --- Matrix Mixer: Activate Mixpoint (route input to output) ---
# Source explicitly flags Toggle Activation as BUG - DOES NOT WORK.
- id: mixpoint_toggle_activation
  label: Mixpoint Toggle Activation (BUG: does not work)
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 06 {idmsb} {idlsb} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((3 * NMIXPOINTS) + 15 + (Mix Point #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((3 * NMIXPOINTS) + 15 + (Mix Point #)) AND 7Fh."
- id: mixpoint_force_activate
  label: Mixpoint Force Activation
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 {idmsb} {idlsb} 7F F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((3 * NMIXPOINTS) + 15 + (Mix Point #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((3 * NMIXPOINTS) + 15 + (Mix Point #)) AND 7Fh."
- id: mixpoint_force_deactivate
  label: Mixpoint Force Deactivation
  kind: action
  command: "F0 00 01 00 {device_id} 0A 69 01 {idmsb} {idlsb} 00 F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((3 * NMIXPOINTS) + 15 + (Mix Point #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((3 * NMIXPOINTS) + 15 + (Mix Point #)) AND 7Fh."

# --- Queries ---
# Each query echoes the command then sends a return string.
# Return string device-ID byte is <Device ID + 10h>.
- id: query_input_mute
  label: Query Input Mute
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 00 {input_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input ID byte: 04h=In1, 05h=In2, 06h=In3, 07h=In4.
- id: query_input_polarity
  label: Query Input Polarity
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 00 {input_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input ID byte: 08h=In1, 09h=In2, 0Ah=In3, 0Bh=In4.
- id: query_input_scaling
  label: Query Input Scaling
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 00 {input_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input ID byte: 0Ch=In1, 0Dh=In2, 0Eh=In3, 0Fh=In4.
- id: query_input_volume
  label: Query Input Volume
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 00 {input_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: input_id
      type: integer
      description: Input volume ID byte: 00h=In1, 01h=In2, 02h=In3, 03h=In4.
- id: query_output_mute
  label: Query Output Mute
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 03 {output_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output mute ID byte: 46h=Out1 .. 4Dh=Out8.
- id: query_output_polarity
  label: Query Output Polarity
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 03 {output_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output polarity ID byte: 4Eh=Out1, 4Fh=Out2, 50h=Out3, 51h=Out4, 52h=Out5, 53h=Out6, 54h=Out7, 55h=Out8.
- id: query_output_scaling
  label: Query Output Scaling
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 03 {output_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output scaling ID byte: 56h=Out1 .. 5Dh=Out8.
- id: query_output_pad
  label: Query Output Pad
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 03 {output_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output pad ID byte: 5Eh=Out1 .. 65h=Out8.
- id: query_output_volume
  label: Query Output Volume
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 03 {output_id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: output_id
      type: integer
      description: Output volume ID byte: 3Eh=Out1 .. 45h=Out8.
- id: query_mixpoint_mute
  label: Query Mixpoint Mute
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 00 {id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = NMIXPOINTS + 15 + (Mix Point #)."
- id: query_mixer_output_mute
  label: Query Mixer Output Mute
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 {idmsb} {idlsb} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + NOUTPUTS + 15 + (NOutput #)) AND 7Fh."
- id: query_mixpoint_polarity
  label: Query Mixpoint Polarity
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 00 {id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = (2 * NMIXPOINTS) + 15 + (Mix Point #)."
- id: query_mixer_output_polarity
  label: Query Mixer Output Polarity
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 {idmsb} {idlsb} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + (2 * NOUTPUTS) + 15 + (NOutput #)) AND 7Fh."
- id: query_mixpoint_volume
  label: Query Mixpoint Volume
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 00 {id} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: id
      type: integer
      description: "<ID> = (Mix Point #) + 15."
- id: query_mixer_output_volume
  label: Query Mixer Output Volume
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 {idmsb} {idlsb} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((4 * NMIXPOINTS) + 15 + (NOutput #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((4 * NMIXPOINTS) + 15 + (NOutput #)) AND 7Fh."
- id: query_mixpoint_activation
  label: Query Mixpoint Activation
  kind: query
  command: "F0 00 01 00 {device_id} 0A 70 {idmsb} {idlsb} F7"
  params:
    - name: device_id
      type: integer
      description: Device ID 0-15.
    - name: idmsb
      type: integer
      description: "<IDMSB> = [((3 * NMIXPOINTS) + 15 + (Mix Point #)) >> 7] AND 7Fh."
    - name: idlsb
      type: integer
      description: "<IDLSB> = ((3 * NMIXPOINTS) + 15 + (Mix Point #)) AND 7Fh."

Feedbacks

- id: input_mute_state
  type: enum
  values: [unmuted, muted]
  description: "Return string: F0 00 01 00 <Device ID+10h> 0A 00 00 04h..07h <VA> 00 F7. <VA>=00h unmuted, 7Fh muted."
- id: input_polarity_state
  type: enum
  values: [positive, negative]
  description: "Return string uses ID 08h..0Bh. <VA>=00h (+), 01h (-)."
- id: input_scaling_state
  type: enum
  values: ["+4 dBu", "-10 dBV"]
  description: "Return string uses ID 0Ch..0Fh. <VA>=00h (+4 dBu), 01h (-10 dBV)."
- id: input_volume_state
  type: integer
  description: "Return string uses ID 00h..03h. <VA> range -60 to +60. Divide by 2 for dB."
- id: output_mute_state
  type: enum
  values: [unmuted, muted]
  description: "Return string uses ID 46h..4Dh. <VA>=00h unmuted, 7Fh muted."
- id: output_polarity_state
  type: enum
  values: [positive, negative]
  description: "Return string uses ID 4Eh, 4Fh, 50h, 51h, 52h, 53h, 54h, 55h. <VA>=00h (+), 01h (-). UNRESOLVED: source polarity set commands list 55h for both Out 7 and Out 8; the query section uses 54h for Out 7 and 55h for Out 8."
- id: output_scaling_state
  type: enum
  values: ["+4 dBu", "-10 dBV"]
  description: "Return string uses ID 56h..5Dh. <VA>=00h (+4 dBu), 01h (-10 dBV)."
- id: output_pad_state
  type: enum
  values: [disengaged, engaged]
  description: "Return string uses ID 5Eh..65h. <VA>=00h off, 01h on."
- id: output_volume_state
  type: integer
  description: "Return string uses ID 3Eh..45h. <VA> range -60 to +60. Divide by 2 for dB."
- id: mixpoint_mute_state
  type: enum
  values: [unmuted, muted]
  description: "Return string uses <ID>=NMIXPOINTS+15+MixPoint#. <VA>=00h unmuted, 7Fh muted."
- id: mixer_output_mute_state
  type: enum
  values: [unmuted, muted]
  description: "Return string uses IDMSB/IDLSB. <VA>=00h unmuted, 7Fh muted."
- id: mixpoint_polarity_state
  type: enum
  values: [positive, negative]
  description: "Return string uses <ID>=(2*NMIXPOINTS)+15+MixPoint#. <VA>=00h (+), 01h (-)."
- id: mixer_output_polarity_state
  type: enum
  values: [positive, negative]
  description: "Return string uses IDMSB/IDLSB. <VA>=00h (+), 01h (-)."
- id: mixpoint_volume_state
  type: integer
  description: "Return string uses <ID>=MixPoint#+15. <VA>=0..127: 0=-Inf, 1-26=-105 to -42.5 dB in 2.5 dB steps, 27-127=-40.0 to +10.0 dB in 0.5 dB steps."
- id: mixer_output_volume_state
  type: integer
  description: "Return string uses IDMSB/IDLSB. <VA>=0..127 same table as mixpoint."
- id: mixpoint_activation_state
  type: enum
  values: [deactivated, activated]
  description: "Return string uses IDMSB/IDLSB. <VA>=00h not activated, 01h activated."

Variables

- id: input_volume
  type: integer
  range: [-30, 30]
  unit: dB
  description: "Per-input channel volume. Control Setting; <VA> = [2 * value] AND 7Fh."
- id: output_volume
  type: integer
  range: [-30, 30]
  unit: dB
  description: "Per-output channel volume. Same formula as input."
- id: mixpoint_volume
  type: integer
  range: [0, 127]
  unit: gain_table
  description: "Mixpoint gain. <VA> = value AND 7Fh. 0=-Inf, 1-26=-105..-42.5 dB @ 2.5 dB, 27-127=-40..+10 dB @ 0.5 dB."
- id: mixer_output_volume
  type: integer
  range: [0, 127]
  unit: gain_table
  description: "Mixer output gain. Same table as mixpoint."
- id: preset
  type: integer
  range: [1, 128]
  description: "Preset number. Sent as preset-1 (0..127) in the recall frame."
- id: device_id
  type: integer
  range: [0, 15]
  description: "Set via DIP switches on the rear of the P4800. Sent as the low nibble of the first byte of the recall frame; sent as a single hex nibble in SysEx frames."

Safety

confirmation_required_for: []
interlocks: []
# UNRESOLVED: source contains no safety warnings, interlock procedures, or power-on sequencing requirements.

Notes

  • Source flags four commands as BUG — DOES NOT WORK: Mixer Output Toggle Mute, Mixer Output Toggle Polarity, Mixpoint Toggle Activation, Mixer Output Change Volume. These are still emitted above for completeness because the source lists them as documented rows.
  • The source polarity set-command section lists Output 7 and Output 8 with the same ID byte 55h (4Eh, 4Fh, 50h, 51h, 52h, 53h, 55h, 55h). The query section uses 54h for Output 7 and 55h for Output 8. The set commands are transcribed verbatim from the source; the discrepancy is in the source, not introduced here.
  • NOUTPUTS equals 8 when no crossover/splitter is in the preset; each crossover/splitter channel reduces it. NMIXPOINTS = 4 * NOUTPUTS.
  • The P4800 requires 5-12 V on DTR; a 1 kOhm resistor to a 5 V supply is documented.
  • Preset recall uses a short 2-byte frame (C h h), not a full SysEx frame; all other commands use the F0h..F7h SysEx frame.
  • After every set or query, the P4800 echoes the command and then sends a return string; the return-string device-ID byte is <Device ID + 10h>.
  • UNRESOLVED: source does not state whether any authentication, pairing, or challenge procedure is required to control the P4800.

Provenance

source_domains:
  - content-files.shure.com
source_urls:
  - https://content-files.shure.com/KnowledgeBaseFiles/p4800_rs232_commands.pdf
retrieved_at: 2026-04-30T04:29:02.308Z
last_checked_at: 2026-09-30T00:44:20.485Z

Verification Summary

verdict: verified
checked_at: 2026-09-30T00:44:20.485Z
matched_actions: 61
action_count: 61
confidence: medium
summary: "All 61 wire-literal actions and transport settings match; the source's documented bugs and polarity ambiguity are preserved. (6 unresolved item(s) noted in Known Gaps.)"

Known Gaps

- "no firmware version or protocol revision stated in source"
- "source lists 55h for both Out 7 and Out 8; the query section uses 54h for Out 7."
- "source polarity set commands list 55h for both Out 7 and Out 8; the query section uses 54h for Out 7 and 55h for Out 8.\""
- "source contains no safety warnings, interlock procedures, or power-on sequencing requirements."
- "source does not state whether any authentication, pairing, or challenge procedure is required to control the P4800."
- "firmware version compatibility not stated in source"

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