Summary
RS-232C serial control spec for the Classe Audio CP-700 stereo preamplifier. Covers input selection, volume, balance, mute, standby/operate, trigger outputs, LCD brightness, tape monitor, IR pass-through, and status queries. All commands and responses are ASCII over serial.
Transport
protocols:
- serial
serial:
baud_rate: 9600
data_bits: 8
parity: none
stop_bits: 1
flow_control: none # UNRESOLVED: flow control not stated; source says 16-byte FIFO, no minimum inter-byte delay
auth:
type: none # inferred: no auth procedure in source
Traits
traits:
- powerable # STBY / OPER commands
- levelable # VOLM / VOL+ / VOL- / BALL / BALC / BALR
- queryable # STAT MAIN / STAT OUTP queries
- routable # MAIN n / INP+ / INP- input selection
Actions
actions:
- id: main_input
label: Select Main Input
kind: action
command: "MAIN{n}"
params:
- name: n
type: integer
description: Input number
notes: "Address prefix P700. may be omitted if uniquely connected."
- id: input_next
label: Step to Next Input
kind: action
command: "INP+"
params: []
- id: input_prev
label: Step to Previous Input
kind: action
command: "INP-"
params: []
- id: output_enable
label: Enable/Disable Output
kind: action
command: "OUTP{n} {x}"
params:
- name: n
type: integer
description: Output number
- name: x
type: integer
description: "1 = enable, 0 = disable"
notes: "Enable (x=1) or disable (x=0) output n."
- id: set_volume
label: Set Volume
kind: action
command: "VOLM{vv.v}"
params:
- name: vv.v
type: string
description: Volume level (e.g. 45.0)
notes: "Sets volume to nearest possible value, mute disengaged."
- id: volume_up
label: Volume Step Up
kind: action
command: "VOL+"
params: []
notes: "Steps volume up, mute disengaged. For acceleration mode, must receive next VOL+/VOL- within 200ms of reply."
- id: volume_down
label: Volume Step Down
kind: action
command: "VOL-"
params: []
notes: "Steps volume down, mute disengaged. Same acceleration timing as VOL+."
- id: mute
label: Mute
kind: action
command: "MUTE"
params: []
notes: "Engages mute and adjusts volume."
- id: unmute
label: Unmute
kind: action
command: "UNMT"
params: []
notes: "Disengages mute, returns to pre-mute volume level."
- id: balance_left
label: Balance Shift Left
kind: action
command: "BALL"
params: []
notes: "Shifts balance 0.5 dB to the left."
- id: balance_center
label: Balance Center
kind: action
command: "BALC"
params: []
notes: "Recenters to even balance."
- id: balance_right
label: Balance Shift Right
kind: action
command: "BALR"
params: []
notes: "Shifts balance 0.5 dB to the right."
- id: standby
label: Standby
kind: action
command: "STBY"
params: []
notes: "Puts CP-700 into standby."
- id: operate
label: Operate
kind: action
command: "OPER"
params: []
notes: "Puts CP-700 into operate mode."
- id: trigger1_off
label: Trigger 1 Off
kind: action
command: "T1_0"
params: []
- id: trigger1_on
label: Trigger 1 On
kind: action
command: "T1_1"
params: []
- id: trigger2_off
label: Trigger 2 Off
kind: action
command: "T2_0"
params: []
- id: trigger2_on
label: Trigger 2 On
kind: action
command: "T2_1"
params: []
- id: lcd_saver
label: LCD Screen Saver
kind: action
command: "LCD0"
params: []
notes: "Sets front panel LCD to low power screen saver mode."
- id: lcd_low
label: LCD Low Intensity
kind: action
command: "LCD1"
params: []
notes: "Sets front panel LCD to low intensity."
- id: lcd_medium
label: LCD Medium Intensity
kind: action
command: "LCD2"
params: []
notes: "Sets front panel LCD to medium intensity."
- id: lcd_high
label: LCD High Intensity
kind: action
command: "LCD3"
params: []
notes: "Sets front panel LCD to high intensity."
- id: ir_pass
label: Pass IR Code
kind: action
command: "IRC{nnn}"
params:
- name: nnn
type: integer
description: IR code from CP-700 IR code table
- id: tape_off
label: Tape Monitor Off
kind: action
command: "TAP0"
params: []
notes: "Turns off tape monitor output."
- id: tape_on
label: Tape Monitor On
kind: action
command: "TAP1"
params: []
notes: "Turns on tape monitor output."
- id: sdp
label: Display AC Module Parameters
kind: action
command: "SDP"
params: []
notes: "Displays AC module parameters."
- id: stat_main
label: Query Main Status
kind: query
command: "STAT MAIN"
params: []
notes: "Requests main volume and input selection."
- id: stat_auto
label: Enable Auto Status Updates
kind: action
command: "STAT AUTO"
params: []
notes: "Enables automatic status updates."
- id: stat_outp
label: Query Output Status
kind: query
command: "STAT OUTP"
params: []
notes: "Requests output status."
- id: stat_off
label: Disable Auto Status Updates
kind: action
command: "STAT OFF"
params: []
notes: "Disables automatic status updates."
Feedbacks
feedbacks:
- id: cmd_ack
type: enum
values: ["!", "?"]
description: "3-byte reply: !\\r\\n = command recognized, ?\\r\\n = command not recognized. Generated within 100ms of receipt."
- id: sy_pwrup
type: string
description: "SY PWRUP - CP-700 has completed power up."
- id: sy_stby
type: string
description: "SY STBY - CP-700 is in standby."
- id: sy_oper
type: string
description: "SY OPER - CP-700 is in operate mode."
- id: sy_volm
type: string
description: "SY VOLM vv.v - Volume level. Appends 'muted' if mute engaged."
- id: sy_main
type: string
description: "SY MAIN n NN - Selected input number n, named NN."
- id: sy_outp
type: string
description: "SY OUTP n x - Output n enabled (x=1) or disabled (x=0)."
Variables
# UNRESOLVED: no settable parameters beyond discrete actions identified in source
Events
events:
- id: power_up_notification
description: "SY PWRUP - sent when CP-700 completes power up."
payload: "SY PWRUP"
- id: standby_notification
description: "SY STBY - sent when CP-700 enters standby."
payload: "SY STBY"
- id: operate_notification
description: "SY OPER - sent when CP-700 enters operate mode."
payload: "SY OPER"
Macros
# UNRESOLVED: no multi-step sequences described in source
Safety
confirmation_required_for: []
interlocks: []
# UNRESOLVED: no safety warnings or interlock procedures in source
Notes
- All commands use ASCII. Command line terminated with CR/LF.
- Address prefix
P700.may be omitted if controller is uniquely connected to the CP-700. - Leading blanks in command strings are ignored.
- Reply generated within 100ms of line feed receipt. If no reply after 100ms, reissue command.
- Volume acceleration mode: VOL+/VOL- must receive next command within 200ms of system reply for acceleration.
- 16-byte FIFO on CP-700; no minimum inter-byte delay required.
Provenance
source_domains:
- support.classeaudio.com
source_urls:
- https://support.classeaudio.com/files/documents/automation_and_control/rs232/CLASSE_CP-700_RS232_Protocol.pdf
retrieved_at: 2026-06-12T02:05:03.516Z
last_checked_at: 2026-06-12T19:14:40.221Z
Verification Summary
verdict: verified
checked_at: 2026-06-12T19:14:40.221Z
matched_actions: 30
action_count: 30
confidence: medium
summary: "All 30 spec actions matched verbatim in source; transport parameters verified; one-to-one coverage. (9 unresolved item(s) noted in Known Gaps.)"
Known Gaps
- "flow control not stated; source says 16-byte FIFO, no minimum inter-byte delay"
- "no settable parameters beyond discrete actions identified in source"
- "no multi-step sequences described in source"
- "no safety warnings or interlock procedures in source"
- "number of inputs and their names not stated in source"
- "number of outputs not stated in source"
- "volume range not stated in source"
- "IR code table not provided in source"
- "other baud rate selections not specified beyond 9600"
From the AI4AV catalog (https://ai4av.net) · ODbL-1.0