Three Communication Methods of ComXim Programmable Turntables

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Introduction

ComXim programmable turntables are designed with flexibility at their core. Whether you are a developer integrating a turntable into an automated 3D scanning pipeline, a photographer setting up a studio workflow, or an engineer deploying a turntable in an industrial environment, having the right communication method makes all the difference.

ComXim turntables support three primary communication interfaces: USB (wired), Wi-Fi (wireless), and Bluetooth BLE 4.0 (wireless). Each method has its own strengths, use cases, and setup requirements. The key advantage of the ComXim ecosystem is that once connected, the control commands are identical across all three methods. This means you can develop your application using one interface and deploy it using another without rewriting your code.

This guide explains each communication method in detail – how they work, how to set them up, and when to choose one over the others.

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The Unified CT Command Protocol

Before diving into the individual communication methods, it is important to understand one fundamental principle: all ComXim turntables use the same CT (ComXim Turntable) command protocol regardless of how you connect.

Whether you send a command over a USB serial port, a Wi-Fi TCP socket, or a Bluetooth BLE connection, the command string is identical:

CT+START(0,1,1,15,2,24);

This unified approach means:

• Write once, deploy anywhere – Your code works across all connection types
• No proprietary SDK required – Plain ASCII text commands work with any programming language
• Consistent behavior – The turntable responds the same way regardless of the connection method

The difference between the three methods lies primarily in the connection process. Once the connection is established, programming and control are identical.

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Method 1: USB (Wired Serial Communication)

Overview

USB is the most stable and reliable communication method for ComXim turntables. It uses a standard USB 2.0 Type‑A to Type‑B cable (the same type used by many printers) and the CH340 USB‑to‑serial chip. After installing the driver, the turntable appears as a virtual COM port on your computer.

Key Characteristics

Feature	Description
Connection Type	Wired (USB 2.0)
Interface	Virtual COM port (CH340 chip)
Baud Rate	115200 (fixed)
Data Bits	8
Parity	None
Stop Bits	1
Flow Control	None
Exclusivity	COM port is exclusive – only one application can use it at a time

Setup Steps

Step 1 – Install the CH340 Driver

Download the driver from the ComXim website: comxim.com/download-usb-driver. The driver is available for Windows, Linux, macOS, and Android.

Step 2 – Connect the Turntable

Use a standard USB 2.0 Type‑A to Type‑B cable to connect the turntable to your computer. Power on the turntable using its external power supply.

Step 3 – Verify the Connection

Open your operating system’s Device Manager (Windows) or equivalent. You should see a new COM port appear under “Ports (COM & LPT)” – for example, COM3, COM4, etc..

Step 4 – Establish Communication

Open your preferred serial communication tool (SSCOM, PuTTY, SecureCRT, or TurntableX). Select the correct COM port, set the baud rate to 115200, and click Connect.

Advantages

• Highest reliability – No interference, no signal dropouts
• Lowest latency – Direct wired connection for real‑time control
• Cross‑platform – Works with Windows, Linux, macOS, and Android
• Ideal for development – Stable connection for debugging and testing
• No battery concerns – Powered by the turntable’s own power supply

Best For

• Software development – Debugging and testing new commands
• Fixed workstation setups – Studio environments where the turntable stays in one place
• Industrial applications – Where reliability is critical
• High‑speed command sequences – Where low latency matters

Code Example (C#)

using System.IO.Ports;

// Create and configure the serial port
SerialPort serialPort = new SerialPort();
serialPort.PortName = "COM3";        // Your COM port
serialPort.BaudRate = 115200;        // Fixed baud rate
serialPort.DataBits = 8;
serialPort.Parity = Parity.None;
serialPort.StopBits = StopBits.One;
serialPort.Open();

// Send a CT command
string cmd = "CT+TURNSINGLE(0,45.0);";
serialPort.Write(cmd);

Code Example (Python)

import serial

# Open the serial port
ser = serial.Serial(
    port='COM3',      # Your COM port
    baudrate=115200,
    bytesize=8,
    parity='N',
    stopbits=1
)

# Send a CT command
cmd = "CT+TURNSINGLE(0,45.0);"
ser.write(cmd.encode())

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Method 2: Wi-Fi (Wireless TCP/IP)

Overview

Wi-Fi enables cable‑free control of the turntable. The turntable creates its own Access Point (AP mode) – a direct point‑to‑point Wi‑Fi network that your computer or mobile device connects to. This is not a connection to your existing home or office network; the turntable generates its own SSID.

Key Characteristics

Feature	Description
Connection Type	Wireless (2.4 GHz Wi-Fi)
Mode	AP (Access Point) – direct point‑to‑point
SSID	Turntable model name (e.g., “MT400RUWPSL100ProV6”)
Default Password	88889999
IP Address	192.168.181.181 (fixed)
Port	8181
Protocol	TCP/IP socket

Setup Steps

Step 1 – Power On the Turntable

Turn on the turntable and wait approximately 10 seconds for it to initialize and broadcast its Wi‑Fi network.

Step 2 – Connect to the Wi‑Fi Network

On your computer or mobile device, open the Wi‑Fi settings and look for a network with the SSID matching your turntable model name (e.g., “MT400RUWPSL100ProV6”). Connect to this network using the default password: 88889999.

Important: The turntable’s Wi‑Fi is for point‑to‑point control only and does not provide internet access. Your operating system may show a “no internet” warning – ignore it and keep the connection. Disconnecting will break control.

Step 3 – Establish a Socket Connection

Once connected to the Wi‑Fi network, create a TCP socket connection to:

• IP Address: 192.168.181.181
• Port: 8181

Step 4 – Send CT Commands

After the socket connection is established, send CT commands as you would over USB – the command format is identical.

Advantages

• No cables – Freedom to place the turntable anywhere within range
• Works with PC and mobile – Connect from any Wi‑Fi‑enabled device
• Simple setup – No network configuration required (AP mode)
• TCP/IP standard – Works with any programming language that supports sockets
• Good for demonstrations – Easy to control from across the room

Best For

• Remote operation – Control the turntable from a distance
• Mobile photography setups – Where cables would be inconvenient
• Demonstrations and trade shows – Clean, cable‑free presentation
• Multi‑device environments – When the turntable needs to be positioned away from the computer

Code Example (Python)

import socket

# Connect to the turntable via Wi-Fi
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(("192.168.181.181", 8181))

# Send a CT command
cmd = "CT+TURNSINGLE(0,45.0);"
sock.send(cmd.encode())

# Receive response (optional)
response = sock.recv(1024)
print(response.decode())

sock.close()

Code Example (Java)

import java.net.Socket;
import java.io.OutputStream;

Socket socket = new Socket("192.168.181.181", 8181);
OutputStream out = socket.getOutputStream();

String cmd = "CT+TURNSINGLE(0,45.0);";
out.write(cmd.getBytes());
out.flush();

socket.close();

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Method 3: Bluetooth BLE 4.0 (Wireless Low Energy)

Overview

Bluetooth BLE (Bluetooth Low Energy) provides a low‑power, wireless connection primarily designed for mobile device control. Unlike traditional Bluetooth that requires pairing, BLE uses a connection‑based model where devices are discovered and connected via UUID matching.

Key Characteristics

Feature	Description
Connection Type	Wireless (Bluetooth BLE 4.0)
Device Name	Turntable model name (first 12 characters, e.g., “MT400RUBL100”)
Pairing	Not required (BLE connection‑based model)
Platform	Primarily Android (demo apps available)
Protocol	BLE GATT (Generic Attribute Profile)
Range	Approximately 3 meters (10 feet)

Setup Steps

Step 1 – Power On the Turntable

Turn on the turntable and wait approximately 10 seconds for it to initialize and broadcast its BLE signal.

Step 2 – Open the TurntableBLE App

ComXim provides a demo Android app called TurntableBLE for Bluetooth control. Download it from the ComXim website.

Step 3 – Scan for Devices

In the app, tap the Scan button. Keep your phone within approximately 3 meters of the turntable. After about 15 seconds, the device list will display available turntables (e.g., “MT320RUBL40”).

Step 4 – Connect

Tap your turntable model in the device list. The app will establish a BLE connection and display the control interface.

Note: The TurntableBLE app is provided as a demo and may not support all Android devices. ComXim has open‑sourced the app source code for developers who wish to build custom versions.

Advantages

• Low power consumption – Ideal for battery‑powered mobile devices
• No pairing required – Simple discovery and connection process
• Mobile‑friendly – Designed for smartphone control
• BLE standard – Works with Android’s built‑in Bluetooth APIs
• Quick connection – Fast to discover and connect

Best For

• Mobile control – Controlling the turntable from a smartphone
• On‑location photography – Where a laptop is impractical
• Quick demonstrations – Simple, cable‑free operation from a phone
• Low‑power applications – When power efficiency matters

Code Example (Android – Conceptual)

// BLE connection (simplified example)
BluetoothManager bluetoothManager = 
    (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
BluetoothAdapter bluetoothAdapter = bluetoothManager.getAdapter();

// Scan for devices with the turntable's name
// Connect using BluetoothGatt
// Once connected, send CT commands via GATT write

// The CT command is the same as USB and Wi-Fi:
String cmd = "CT+TURNSINGLE(0,45.0);";
// Write to the characteristic

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Comparison Table

Feature	USB	Wi-Fi	Bluetooth BLE
Connection Type	Wired	Wireless (AP mode)	Wireless (BLE)
Setup Complexity	Medium (driver required)	Low (connect to SSID)	Low (scan and connect)
Reliability	★★★★★	★★★★	★★★
Latency	Lowest	Low	Moderate
Range	Cable‑limited	Room‑scale (~30m)	Short (~3m)
Power Consumption	N/A (device powered)	Moderate	Low
Platform Support	Windows, Linux, macOS, Android	Any with TCP/IP	Primarily Android
Best For	Development, fixed setups	Remote control, demonstrations	Mobile control
Model Indicator	U in model name	W in model name	B in model name

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Choosing the Right Communication Method

USB If:

• You are developing and debugging software
• You need the most reliable connection
• Your turntable is in a fixed location
• You require lowest latency for precise control
• You are working in an industrial or studio environment

Wi-Fi If:

• You want cable‑free operation
• You need to control the turntable from across the room
• You plan to use both PC and mobile devices
• You are doing demonstrations or trade shows
• You want simple setup without drivers

Bluetooth If:

• You primarily use a smartphone for control
• You need low‑power wireless operation
• You want a quick, simple connection process
• You are working in mobile photography setups

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Important Notes

Wi‑Fi and Bluetooth Are Mutually Exclusive

A single turntable model cannot have both Wi‑Fi and Bluetooth. Check the model name:

• W = Wi‑Fi support
• B = Bluetooth support

Model Compatibility

Not all turntable models support all three communication methods. Look for the appropriate letter in the model name:

• U = USB support
• W = Wi‑Fi support
• B = Bluetooth support

The Commands Are Always the Same

Once connected, the CT commands are identical regardless of the communication method. This means you can develop with USB and deploy with Wi‑Fi, or test with Bluetooth and scale to USB – all without rewriting your command logic.

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Troubleshooting Common Issues

USB Connection Issues

Issue	Solution
COM port not visible	Install CH340 driver
Wrong COM port	Check Device Manager for the correct port
Connection refused	Close other applications using the same COM port
Baud rate mismatch	Ensure baud rate is set to 115200

Wi‑Fi Connection Issues

Issue	Solution
SSID not visible	Wait 10 seconds after power‑on for the AP to start
Wrong password	Default password is 88889999
Connection drops	OS may disconnect “no‑internet” networks – select “Keep Connection”
Cannot connect to IP	Ensure you are connected to the turntable’s Wi‑Fi network

Bluetooth Connection Issues

Issue	Solution
Device not found	Stay within 3 meters of the turntable
App not compatible	TurntableBLE supports only some Android devices
Connection fails	Grant location and Bluetooth permissions to the app

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Conclusion

ComXim programmable turntables offer three flexible communication methods – USB, Wi‑Fi, and Bluetooth – each designed for different use cases and environments. The key advantage is that all three methods use the same CT command protocol, so you can develop once and deploy anywhere.

Summary:

• USB – Most reliable, lowest latency, ideal for development and fixed setups
• Wi‑Fi – Cable‑free, works with PC and mobile, ideal for remote control
• Bluetooth – Low‑power, mobile‑friendly, ideal for smartphone control

Choose the method that fits your workflow today, and know that you can always switch to another method without rewriting your command logic.

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Additional Resources

Resource	Link
Official Website	comxim.com
USB Driver Download	comxim.com/download-usb-driver
Developer Tools	comxim.com/development-kit
Software & Apps	comxim.com/softwareapps-demo
Latest CT Command List	comxim.com/the-new-command-list
Developer Help Center	comxim.com/developer-help-center