Terminal management via RS232 and API

TrueConfAbout 32 min

Terminal management via RS232 and API

Terminal TrueConf Group allows control not only via the remote and web interface, but also through text commands (Command Line Interface) via the physical RS-232 port, using a USB to RS-232 adapter (for instance, if the built-in port is occupied by a PTZ camera), and remotely via the SSH protocol.

For testing terminal management via commands, you can use specific software depending on the operating system: PuTTY for Windows OS and the minicom utility for Linux OS.

This feature also enables easy integration of TrueConf Group into meeting room control systems (e.g., TrueConf Coordinator), allowing you to add terminal control buttons to the tablet interface.

RS-232

You can use the RS-232 port or a USB to RS-232 adapter to send control commands to the terminal. To do this:

In the control panel, go to the RS-232 Interfaces section, and on the General tab, set a password for connecting to the RS-232 API, or leave it as default.
Connect the computer to the codec using an RS-232 cable.
Go to the HARDWARE tab (or USB 1 if using a USB - RS-232 adapter), select the RS-232 API option from the Role dropdown menu, and configure the port settings:
- Speed (bit/s) - the number of bits transmitted per second (bps) or the number of signal changes per second.
- Data bits - the number of bits that encode a single transmitted character (letters, numbers, etc.).
- Parity - A method for error detection in data transmission by adding an extra bit to each data unit.
  - None - default value, no additional bit is added.
  - Even The total number of 1 bits in each character is counted, and if necessary, an additional bit 1 or 0 is added to make the total number even.
  - Odd - The number of 1s in each character is counted, and if necessary, an additional bit of 1 or 0 is added to make the total count odd.
  - Mark - An extra bit 1 is added to each character.
  - Space - an additional bit 0 is added to each character.
- Stop bit - An additional bit that indicates where one character ends and the next one begins. The more stop bits there are, the "longer the pause" between characters.
- Flow control - a type of data flow control that allows pausing and resuming data transmission when the receiving device is unable to process information in a timely manner.
  - None - default value, flow control is disabled.
  - Xon / Xoff - software control method where the device sends special characters Xoff (Ctrl+S, code 0x13) and Xon (Ctrl+Q, code 0x11).
  - Hardware - a hardware control method that uses additional contacts in the connector. When controlled via RS-232, the device sends a signal through special contact No. 4 RTS (Request To Send) and No. 5 CTS (Clear To Send).
Connect to the codec using SSH as shown in the SSH section.
Run the listdevice command to display the list of connected devices. Under the header Available serial devices, find id=ttyUSB0 (most often 0). In this case, the connected RS-232 port is named ttyUSB0.
Execute the command setdevice serial ttyUSB0. If successful, the output should be: Serial port "ttyUSB0" selected successfully.

The methods for executing commands vary depending on the operating system:

For Windows OS, use a special program like PuTTY and similar ones.
For Linux OS, using the minicom utility.

SSH

How to Connect

The ability to authenticate in CLI TrueConf Group via SSH is restricted by the terminal's operating system settings. After three failed login attempts (incorrect password entries), the connection is blocked. To remove the block, you need to restart the terminal or reboot its operating system.

Step 1. To connect to the terminal from the command line, you first need to set up an access key on the device from which you will be connecting to TrueConf Group:

In the control panel, go to section Settings → Maintenance → Permissions → SSH.
Click the Download new access key button.
Move the downloaded id_rsa key to the folder:
- On Windows OS, the default path is: C:\Users\Username\.ssh
- In Linux OS, the default is: /Username/.ssh

Step 2. Now you need to connect using an SSH client. Use the login tcgsh:

Install (if you have not done it before) and run an SSH client; for example, you can use the OpenSSH package or any other. In many operating systems, it is available out of the box; for example, on Windows 10, you just need to run the following command:
```
ssh tcgsh@[group_ip]
```
where [group_ip] is the IP address of your endpoint.
If a WARNING: UNPROTECTED PRIVATE KEY FILE! error appears when connecting to the terminal, you need to change the access permissions for the id_rsa private key file. To do this, enter the command chmod 600 id_rsa in the directory of the private key.
The CLI welcome text TrueConf Group will appear. You can now enter any supported commands:

user@linux:~$ ssh tcgsh@10.160.2.55
Last login: Thu Apr 23 17:46:26 2026 from 10.160.2.12
Welcome to TrueConf Group Management Shell 2.1.0.15
(tcg cli)

Commands sent to the terminal are case-insensitive. For example, you can enter the command as HELP, help, or Help.

To view the list of commands, type HELP.

To view information about the specific command [command], run [command] HELP.

The parameters (if they are present) have to be specified separated by a whitespace, for example, the command

CALLHISTORY 10

will list 10 most recent entries from the call history.

Control Commands

ABOOK

Add a contact to the address book.

Parameter	Description
ADD [NAME] [PROTO]:[ADDRESS]	Add a contact to the address book, where: NAME is the display name, PROTO is the protocol (sip, h323, rtsp, vnc, ndi), and ADDRESS is the address used for the call. Example command: `ABOOK ADD ALEX sip:10.110.2.240`
DEL [NAME]	Delete the contact with the specified name

ANSWER

Accept an incoming call

Parameter	Description
VIDEO	Accept an incoming call if auto-answer is disabled. This can be checked in the control panel in the section.

AUDIOCODEC

Enable or disable the audio codec.

Parameter	Description
[CODEC] ON	Allow the use of audio codec [CODEC]
[CODEC] OFF	Disable the use of audio codec [CODEC]
[CODEC] GET	Get the current status of the codec [CODEC]
GET	Get the current status of all audio codecs

See the list of all codecs supported by the terminal in the section "TrueConf Group Capabilities".

AUDIOMUTE

Microphone control.

Parameter	Description
ON	Mute microphone
OFF	Enable microphone
GET	Get the current microphone status
REGISTER	Receive notifications about microphone status changes. If the terminal operator turns the microphone on or off, corresponding notifications will be displayed in the console. These messages will be received until they are disabled using the `UNREGISTER` command and will only be available in the current SSH connection session.
UNREGISTER	Disable microphone status change notifications

AUTOANSWER

Settings for automatic call pick-up.

Parameter	Description
YES	Automatic acceptance of the first incoming call. Similar to setting the parameter value.
NO	Disabling auto-answer for incoming calls. This is similar to setting a value for the parameter.
DND	Blocking incoming calls; all calls will be automatically declined. This is similar to setting the value in the section
GET	Get the current value of the auto-answer parameter

CALLINFO

Get information about the current call

The command displays technical information about one or more active connections (in case of using the MCU function). The CallID parameter is required for call identification and is used in other commands. Example of how the command works:

TCG console>CALLINFO
Active calls:
CallID:"8"
       Direction:Outgoing
       Contact URI:"sip:222@example.com"
       User agent:"TrueConf Server 5.4.5.10072"
       Duration:230 sec
       Bitrate:"1008"
Audio in: Compression:"G.722.1C (32 kbit/s)", Bitrate:"32", Packets:"11304", Lost packets:"0", Loss rate:"0"%, Jitter:"30"
Audio out: Compression:"G.722.1C (48 kbit/s)", Bitrate:"48", Packets:"11301", Lost packets:"0", Loss rate:"0"%, Jitter:"10"
Video in: Codec:"H264", Bitrate:"960", Resolution:"1280x720", Frame rate:"27", Packets:"35495", Lost packets:"0", Lossrate:"0%", Jitter:"11%"
Video out: Codec:"H264", Bitrate:"960", Resolution:"1280x720", Frame rate:"30", Packets:"39959", Lost packets:"0", Lossrate:"0%", Jitter:"2%

CALLHISTORY

Get call history

Parameter	Description
N	The number of recent calls to display, with the default being N=5.

CAMERA

PTZ camera control

Parameter	Description
LEFT, RIGHT, UP, DOWN	Rotate the camera to the left, right, up, or down accordingly.
ZOOM+, ZOOM-	Zoom in or out of the image
STOP	Stop camera movement
POSITION SAVE [n]	Save the current camera position (preset) as number `[n]`
POSITION LOAD [n]	Move the camera to position (preset) number `[n]`.
POSITION CLEAR [n]	Remove camera position (preset) with number `[n]`.

You can verify the camera settings in the terminal control panel under section Settings → Devices → Camera.

CAMERAMUTE

Camera video stream control

Parameter	Description
ON	Disable video stream from the camera
OFF	Enable video stream from the camera
GET	Get the current camera status
REGISTER	Subscribe to receive notifications for camera off/on events: relevant notifications will be displayed in the console. These messages will be received until they are disabled using the `UNREGISTER` command and only during the current SSH session.
UNREGISTER	Disable notifications about camera status changes

CONTENT

Content display management. The content source must be selected in advance using the remote control or on the Conference control panel tab.

Parameter	Description
GET	Display the current status of content sharing
PREVIEW	Enable content preview without sending it to the conference
REGISTER	Receive notifications about content sharing status changes from the terminal.
SHARE	Start streaming content to the conference
STOP	Stop content sharing

CORETEMP

Get the endpoint CPU temperature.

Command and response example:

(tcg cli) CORETEMP
CPU temperature: +50.0°C

DIAL

Call to a user

Parameter	Description
URI	Make an outgoing call to the specified URI.

Then, depending on your actions, the following notifications will be displayed:

Incoming call
Outgoing call
Hangup call
Dial failed

DTMF

Send a DTMF code CODE to the user with ID [CallID]. The code consists of digits and usually ends with #.

Parameter	Description
[CallID]	Call ID for sending the command. If there is only one active connection with the terminal at the time of sending the command, this parameter can be omitted.
CODE	The sequence of DTMF symbols that should be sent to the subscriber. The special character `P` adds a 100 ms pause.

When the code has been sent, the corresponding notification will be displayed, for example, the code 111# has been sent to the user with the ID 272:

(tcg cli) DTMF 272 111#
DTMF code passed successfully

HANGUP

End a call.

Parameter	Description
VIDEO [CallID]	Terminate the connection with ID `[CallID]`. The call identifier value `[CallID]` is displayed when the connection is established, as shown in the Outgoing call notification example.
ALL	End all current connections

Command result example:

TCG console>hangup video 266
Hangup the video call [266] passed
TCG console>
Hangup call [266]:
        Name:"Room"
        Contact URI:"h323:room@video.company.com:1720"
        Protocol:"H.323"

HOSTNAME

Get or set the system name.

Parameter	Description
SET [NAME]	Set the system name. A corresponding message will then be displayed.
GET	Display the system name

How to get the name or set a new one:

(tcg cli) hostname get
System hostname:"TrueConf Group"
(tcg cli) hostname set New name
Hostname "New name" set successfully

IP

Obtain the IP address TrueConf Group.

Parameter	Description
ADDRESS	Display IP address
ROUTE	Display routing table

The result of the IP ADDRESS command:

(tcg cli) ip address
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether fc:34:97:67:62:5f brd ff:ff:ff:ff:ff:ff
    inet 10.160.2.55/22 brd 10.160.3.255 scope global noprefixroute dynamic eth0
       valid_lft 22589sec preferred_lft 22589sec
    inet6 fe80::d2c4:ad3a:e4f8:b569/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

The result of the IP ROUTE command:

(tcg cli) ip route
default via 10.160.0.1 dev eth0 proto dhcp metric 100 
10.160.0.0/22 dev eth0 proto kernel scope link src 10.160.2.55 metric 100

LAYOUT

Video layout management in group conferences using the MCU function or in a point-to-point call when self-view is displayed (i.e., a layout with 2 video windows). For more details on layouts, refer to the "Video Layout Management" section in the user documentation.

Parameter	Description
EQUAL	Set a uniform video layout
TOP	Set the layout with the priority window on top
BOTTOM	Set the layout with the priority window at the bottom
LEFT	Set the layout with the priority window on the left
RIGHT	Set the video layout with the priority window on the right
AUTO	Set automatic video layout
GET	Get the current video layout type

LISTDEVICE

Get the list of available audio and video devices connected to the endpoint.

Parameter	Description
Without parameter	Display information about all audio/video devices
AUDIO	Retrieve the list of all audio devices connected to the terminal.
AUDIO CAPTURE	Obtain a list of all audio capture devices connected to the terminal
AUDIO RENDER	Retrieve the list of all audio playback devices connected to the terminal.
VIDEO	Obtain a list of all video devices connected to the terminal.
VIDEO CAPTURE	Retrieve the list of all image capture devices connected to the terminal.
VIDEO RENDER	Retrieve a list of all output devices (displays) connected to the terminal.
SERIAL	Retrieve the list of connected serial ports. This can be used to identify connected external USB-RS232 adapters.

When using any of the commands, each device displays its identifier in the id parameter. This identifier is used when executing other equipment-related commands, such as selecting a device with SETDEVICE.

How to get the list of all audio and video devices:

(tcg cli) listdevice

Available audio capture devices:
         id="1", "Line in", active:False, default:False, level:100%, boost:0, aec:0, agc:False, noise suppressor:False
         id="2", "HDMI1", active:False, default:False, level:100%, boost:0, aec:0, agc:False, noise suppressor:False
         id="3", "HDMI2", active:False, default:False, level:100%, boost:0, aec:0, agc:False, noise suppressor:False
         id="4", "eMeet M2 [USB Audio]", active:True, default:False, level:100%, boost:0, aec:0, agc:False, noise suppressor:False
Available audio render devices:
         id="1": "Display port", active:False, default:False, level:86%
         id="2": "HDMI", active:False, default:False, level:52%
         id="3": "Line out", active:False, default:False, level:17%
         id="4": "eMeet M2 [USB Audio]", active:True, default:False, level:4%
         id="5": "All outputs", active:False, default:False, level:50%
Available video capture devices:
         id="1": "Clevermic 1212U/HD Camera", video:1280x720@60.01
         id="2": "HDMI1/MZ0380:RAW 00.00 12abf55f", video:1920x1080@0.0
         id="3": "HDMI2/MZ0380:RAW 01.00 12abf55f", video:1920x1080@0.0
         id="4": "USB/file", video:1920x1080@25.0
Available video render devices:
         id="1": "BenQ GL2460", port: HDMI", active:True

MULTIPOINT

Managing the MCU feature.

Parameter	Description
ON	Enabling MCU Mode
OFF	Disabling the MCU feature
GET	Display the current status of the MCU function

PROTOCOL

SIP and H.323 settings.

Parameter	Description
PROTOCOL SIP [ON/OFF]	Enabling/disabling operation via SIP protocol
PROTOCOL H323 [ON/OFF]	Enable/disable operation via the H.323 protocol
PROTOCOL SIP SRTP [ON/OFF/MANDATORY]	Management of SRTP encryption usage in calls over the SIP protocol: `ON` — encryption is preferred but not mandatory; `OFF` — not used; `MANDATORY` — the terminal will not connect with subscribers who do not support SRTP.
PROTOCOL H323 H235 [ON/OFF/MANDATORY]	Managing the use of H.235 encryption for calls using the H.323 protocol: `ON` — encryption is preferred but not mandatory; `OFF` — encryption is not used; `MANDATORY` — the terminal will not connect with subscribers who do not support H.235.
PROTOCOL SIP GET	Display the current status of SIP protocol usage
PROTOCOL H323 GET	Display the current status of H.323 protocol usage.
PROTOCOL SIP SRTP GET	Display the current status of SRTP encryption usage for SIP calls.
PROTOCOL H323 H235 GET	Display the current status of H.235 encryption usage for H.323 protocol calls.

It is impossible to disable both SIP and H.323 at the same time. If one of them is disabled, and a user tries to disable the second one, the former will be automatically activated.

REBOOT

Restart TrueConf Group.

The command is similar to pressing the Restart OS button in the Settings → Power → Power management section of the terminal control panel.

This command is executed right after being sent without any preliminary confirmation request (unlike a similar action in the control panel).

RCKEY

Send the code of the button on the remote control to execute the corresponding command as if the button were physically pressed.

Parameter	Description
KEY	Remote control button code. Valid values: `0..9`, `*`, `#`, `HOME`, `BACK`, `MENU`, `OK`, `LEFT`, `RIGHT`, `UP`, `DOWN`, `DIAL`, `BACKSPACE`, `HANGUP`, `PC`, `FARNEAR`, `LAYOUT`, `ZOOM+`, `ZOOM-`, `VOL+`, `VOL-`, `POWER`.

Example of the command for zooming in the image from the PTZ camera connected to the endpoint:

(tcg cli) rckey zoom-
RCKEY passed successfully

SELFVIEW

Set the mode for displaying the self-view on the endpoint screen (this configuration will not affect the way in which the self-view will be displayed in the layout).

Parameter	Description
ON	Display local video
OFF	Hide self-view video
TOGGLE	Switch local video
GET	Request local video status

SETDEVICE

Select the device for capturing or playing media streams and content sharing.

The commands listed below use the DeviceId parameter, which is the device identifier. It can be obtained using the command LISTDEVICE.

Parameter	Description
AUDIO CAPTURE [DeviceId]	Select the `DeviceId` device for audio capture.
AUDIO RENDER [DeviceId]	Select the `DeviceId` device for audio output.
VIDEO CAMERA [DeviceId]	Select the `DeviceId` device for capturing the main video stream (as a camera).
VIDEO PRESENTATION [DeviceId]	Select the `DeviceId` device for capturing an additional video stream (as content).
SETDEVICE VIDEO PRIMARY [DeviceId]	Select the display for showing the main video stream
SETDEVICE VIDEO SECONDARY [DeviceId]	Select a display to show the additional video stream.
VIDEODUAL ALL	Enable second display
VIDEODUAL OFF	Disable the second display
VIDEODUAL MIRROR	Mirroring the primary monitor's display on the second screen
VIDEODUAL PRESENTATION	Display an additional stream (shared content) on the second monitor.

SHUTDOWN

Turn off TrueConf Group.

The command is similar to pressing the Shut down the endpoint button in the Settings → Power → Power management section of the terminal control panel.

This command is executed right after being sent without any preliminary confirmation request (unlike a similar action in the control panel).

SPEAKERMUTE

Audio playback settings.

Parameter	Description
ON	Disable audio output
OFF	Enable audio output
GET	Request audio output status
REGISTER	Subscribe to receive notifications for audio output being turned on or off: relevant notifications will be displayed in the console. These messages will continue to be received until they are disabled using the `UNREGISTER` command and only during the current SSH connection session.
UNREGISTER	Disable notifications for audio output status changes

VIDEOCODEC

Enable or disable the video codec.

Parameter	Description
[CODEC] ON	Allow the use of video codec [CODEC]
[CODEC] OFF	Disable the use of video codec [CODEC]
[CODEC] GET	Get the current status of the codec [CODEC]
GET	Get the current status of all video codecs

See the list of all codecs supported by the terminal in the section "TrueConf Group Capabilities".

VIDEOMIXER

Set the stream mixing mode for multipoint control unit (MCU).

Parameter	Description
VIDEOLESSON	In the video lecture mode, participants can only see and hear the moderator, who is represented by the terminal. However, all participants can hear each other.
ALL	The "everyone on screen" mode, where all participants can see and hear each other
ACTIVESPEAKER	The voice activation mode allows everyone to see and hear each other, with the active speaker displayed in the priority window of the video layout.

VOLUME

Volume settings

Parameter	Description
UP	Increasing the volume level
DOWN	Lowering the volume level
GET	Display the current volume level (in percentage) in the console.
REGISTER	Subscribe to notifications for volume increase/decrease: the console will display `event: volume up` and `event: volume down` messages, respectively. These messages will be received until they are disabled with the `UNREGISTER` command, and only during the current SSH session.
UNREGISTER	Disable notifications for volume changes

It is also possible to change the volume level with the commands RCKEY VOL+ and RCKEY VOL-.

WAKEON

Power management of TrueConf Group via LAN port using Wake-on-LAN (WoL) technology.

Parameter	Description
[MODE]	WoL operating modes: p – wake on PHY; u – wake on unicast messages; m – wake on multicast messages; b – wake on broadcast messages; g – wake on MagicPacket messages.
OFF	Disabling WoL technology
GET	Get WoL status

WHOAMI

Displaying information about TrueConf Group.

Command result example:

(tcg cli) whoami
Information about the system:
	Display Name:"TrueConf Group"
	Serial Number:"TCG01B9209863"
	License Type:"permanent"
	Software version:"1.1.0.470"
	IP address:"10.160.2.55"
	MAC:"FC:34:97:67:62:5F"
	SIP:"sip:10.160.2.55"
	H323:"h323:10.160.2.55"
	H323 Gatekeeper:""
	SIP Server:""
	H323 Name:""
	H323 Extension:""
	Display information:
	  Name:""
	  Connected:"True"
	  Active:"True"
	  Mode:"3840x2160@30.0 [30.0]"

Notifications

audiomute off

The microphone has been unmuted.

audiomute on

The microphone has been muted.

cameramute off

The camera has been turned on.

cameramute on

The camera has been turned off.

исходящий поток контента начат

TrueConf Group started content sharing as a second stream in a call or conference.

исходящий поток контента остановлен

TrueConf Group stopped content sharing.

Dial failed

The call has ended before it could be received (e.g., by timeout).

Hangup call

A notification upon the termination of a session with a specific subscriber. Pay attention to the ID [259], which is the call identifier [CallID] that also appears in the output of the CALLINFO, HANGUP commands, and in the Incoming call, Outgoing call notifications.

For example:

Hangup call [259]:
	Name:"Jhon Doe"
	Contact URI:"h323:doe@10.110.2.240:1720"
	Protocol:"H.323"

Incoming call

The notification displayed when:

An incoming call is made (in this case, the word ringing will also be included)
An incoming call is answered (in this case, the word confirmed will be included).

Please note the ID [260] in the examples below—this is the call identifier [CallID]. This ID is also displayed in the output of the CALLINFO, HANGUP commands, and in the Outgoing call, Hangup call notifications.

Example of a notification about an incoming call that has not been answered yet:

Incoming call [260], ringing:
	Name:"Joe Smith"
	Contact URI:"h323:111@video.example.com:1720"
	Protocol:"H.323"
	User agent:"TrueConf Gateway 4.3"

An example of a notification displayed when a call is answered:

Incoming call [260] confirmed:
	Name:"Joe Smith"
	Contact URI:"h323:111@video.example.com:1720"
	Protocol:"H.323"
	User agent:"TrueConf Gateway 4.3"

Outgoing call

The notification displayed when:

When a call is made from the endpoint, the word ringing will be included;
When a user answers a call from the endpoint, the word confirmed will be included.

Please note the ID [259] in the examples below – this represents the call identifier [CallID]. This ID is also displayed in the output of the CALLINFO, HANGUP commands, and in the notifications for Incoming call, Hangup call.

Example of a notification about an outgoing call that has not been answered yet:

Outgoing call [259], ringing:
	Name:"111"
	Contact URI:"h323:111@10.110.2.240:1720"
	Protocol:"H.323"
	User agent:""

An example of a notification displayed when a call is answered:

Outgoing call [259] confirmed:
	Name:"111"
	Contact URI:"h323:111@10.110.2.240:1720"
	Protocol:"H.323"
	User agent:"TrueConf Gateway 4.3"

speakermute off

The audio playback device has been turned on.

speakermute on

The audio playback device has been turned off.

REST API

TrueConf Group supports OAS3 — the OpenAPI version 3 specification.

Access to API

Go to the Settings → Maintenance → Permissions → API section to restrict API access:

Enter Username and Password.
Click Apply.

You can now connect to TrueConf Group via REST API using the provided credentials.

If you forgot your password, click Reset and enter new information.

Features

With the API, you can:

view and edit the address book;
make calls;
control connected equipment;
configure;
manage network settings;
restart the OS, shut down or reboot the terminal;
configure time and NTP;
create SSH keys;
Configuring and managing a connected tablet;
and much more.

Help with the API

The REST API documentation is embedded in terminal TrueConf Group. To access it, go to https://{IP}/api/v1/doc, where {IP} is the terminal's IP address, for example, 10.110.2.220/api/v1/doc. The documentation is also available at https://developers.trueconf.com/group/api/.

If you have any questions regarding the product or API, you can ask them in our Telegram community.