Understanding the Serial Cable to USB: What is it?

USB to Serial Adapter (RS232)

A USB to Serial adapter, also known as an adapter cable, is an easy way to add one or more RS232 serial ports to a computer. On this page you will find our RS232 versions with one, two or four serial ports in one converter, which means that you can add up to four serial RS232 ports to one computer.

The installation process is relatively easy. First you download the drivers for the USB to serial adapter from our website. Then unzip the downloaded file and install the drivers on your computer by clicking on the installation file. Once the installation is complete you can connect the USB to serial adapter to your computer and the operating system (Windows or Mac) will create a virtual COM port which will show up in Device Manager.

Definition and Purpose

A USB to serial adapter is a device that converts a USB signal to a serial signal, allowing users to connect serial devices to a computer via a USB port. The primary purpose of a USB to serial adapter is to provide a connection between a computer and a serial device, such as a printer, scanner, or GPS device, when the computer does not have a built-in serial port. This makes it an essential tool for modern computers that lack native serial ports, enabling seamless communication with a wide range of serial devices.

GOOD	BETTER	BEST

USB Serial Adapter PRO	USB Serial Adapter Ultimate	USB Serial Adapter Thunderlinx™

The USB to Serial Adapter - Generally

A USB to serial adapter, also referred to as a USB serial converter or RS232 adapter is a small electronic device which can convert a USB signal to serial RS232 data signals. RS232 is the type of signal which is in many older PCs and is referred to as a serial COM port.

A USB to serial adapter typically converts between USB and either RS232, RS485, RS422, or TCP signals, functioning similarly to a serial cable. However, some USB to serial adapters have other special conversion features such as custom baud rates, high-speed or other.

Even the USB to serial adapter RS232 standard is an older communication protocol it is still used by many modern serial RS232 devices in both business and consumer markets and is also often used for personal and office serial devices. More recently most new computers do not have a built-in COM port so a USB serial adapter is often used for connecting many types of serial devices to a computer. A standard USB to serial adapter is a very useful device for connecting equipment such as printers, scanners, scales and GPS devices, but also most business and consumer equipment can be connected to a computer by using an industrial grade adapter.

The USB serial adapter is made in different versions and grades, the 1-port adapter is very popular and one of the most commonly used adapters. Two to four port adapters are also frequently used if the user needs more than one serial port. Multi-port adapters can be connected to a computer by using just one USB cable, where after the computers operating system will create multiple virtual COM ports. Grades range from standard consumer grade to industrial grade and even mission critical grade adapters. Most consumer grade USB serial adapters are not optically isolated or protected against high voltage spikes however most industrial grade adapters are optically isolated which means they are protected against voltage spikes and surges, ground-loops and most other voltages which potentially can damage the adapter or the connected serial devices.

The serial RS232 protocol has existed since the early 60’ties so you may wonder why it is still being used today. The reason is that it is a very reliable way of data communication and it is fairly easy to understand for engineers so it’s easy to develop and program new devices. Another reason is that since the serial protocol has existed for such a long time, many devices already have the serial protocol built-in so its easy to integrate new devices with old devices.

A USB to Serial adapter is an easy way to add one or more RS232 serial ports to a computer. On this page you will find our RS232 versions with one, two or four serial ports in one converter, which means that you can add up to four serial RS232 ports to one computer.

How to install and use a USB to Serial adapter (RS232)

If you have a device with a serial port and you need to connect it to a computer, then you can use a USB to Serial adapter, since most modern computers doesn’t have a native serial port. A USB adapter can also be used in industrial applications to facilitate RS-232 modem control in challenging environments. Only computers in the old days had a serial COM port. Fortunately modern computers has USB ports which can be used for converting serial data from USB to serial RS232 and also from serial to USB, almost all converters will convert data in both directions.

Installing the drivers

The first thing you need to do when connecting a USB to serial RS232 adapter to your computer is to install the drivers for the adapter. Drivers are a small collection of files which will be installed on your computer. These files will tell the operating system how to use/communicate with the USB to serial adapter's hardware and how to convert the data.
The drivers can be downloaded for free from our website here:

Drivers for the USB to Serial adapter

The download consists of a zip file. To install the drivers simply unzip the downloaded file and navigate to the folder with the operating system you are using, then run the exe file with the driver installation program.

Once the drivers are installed successfully you can connect the USB end of the USB to Serial adapter (RS232) to your computer's USB port and the adapter is ready to use.

Accessing and using multiple virtual COM ports

To be able to access and use the virtual serial COM port created by the drivers and Windows, you need to find out which COM port number has been assigned by Windows.
With the USB to Serial adapter connected to your computer you open Windows Device Manager and click on the "Ports (COM & LPT) tab. Under this tab the all COM ports in your computer will be listed. In the example below, COM port 25 is the virtual serial COM port for the USB to Serial adapter. The two other COM ports are native COM ports in this example.

If you right-click on the virtual RS232 COM port and click on Properties, you will be able to see the serial port's settings, and under Advanced you will be able to change the COM port number assigned to the USB to serial adapter. The COM port number can be any number between 1 and 255, as long as it's not already in use by the system.

Types and uses

As mentioned earlier, there are several types of USB to Serial adapters. Here are the overall categories / types:

USB to Serial RS232 adapter
USB to Serial RS485 adapter
USB to Serial RS422 adapter
Multi-port USB to Serial adapters
Isolated USB to Serial adapters
Industrial grade USB to Serial adapters

Obviously, a USB to Serial RS232 adapter is used for communicating with a RS232 serial device and a USB to RS485 / 422 adapter is used for communicating with a RS485 or RS422 device respectively. Adapters that combine all three interfaces into one adapter is also available, so you don't need three individual adapters if you have three different types of devices.

Multi-port adapters are USB to serial adapters which has more than one COM port. It can be for example two, four, six, eight, sixteen or even thirty-two COM ports in one adapter. The ports can be either the same type (RS232) or a combination of RS232, RS485 and RS422 ports.

Isolated USB to Serial adapters are designed not only to convert data but also to isolate the connected devices from each other. For example, if you want to isolate your computer from the connected serial device for safety reasons. Isolation makes sure that if there are voltage spikes, surges, ground-loops or other voltages that can damage either the computer or the device, then they are isolated from each other, which will protect at least one of the devices.

Serial Port Connectivity

Serial port connectivity refers to the ability of a device to communicate with a computer through a serial interface. Serial ports use a single wire to transmit data one bit at a time, making them a reliable choice for many industrial and commercial applications. USB to serial adapters provide a convenient way to connect serial devices to computers that do not have built-in serial ports, ensuring that older and specialized equipment can still be used with modern systems.

Choosing the Right Adapter

Choosing the right USB to serial adapter depends on several factors, including the type of serial device being connected, the operating system of the computer, and the desired level of performance. Some key considerations include:

Compatibility: Ensure the adapter is compatible with the computer’s operating system and the serial device being connected.
Speed: Choose an adapter that supports the desired baud rate and data transfer rate.
Isolation: Consider an adapter with optical isolation to protect against voltage spikes and surges.
Number of ports: Select an adapter with the required number of serial ports.

By taking these factors into account, users can select the most suitable USB to serial adapter for their specific needs, ensuring reliable and efficient communication between their computer and serial devices.

Troubleshooting Common Issues

Common issues with USB to serial adapters include:

Driver installation problems: Ensure the correct drivers are installed and updated.
Connection issues: Check the adapter and serial device connections, and ensure the adapter is properly configured.
Data transfer errors: Check the baud rate and data transfer rate settings, and ensure the adapter is properly configured.
Compatibility issues: Ensure the adapter is compatible with the computer’s operating system and the serial device being connected.

By following these troubleshooting steps, users can quickly identify and resolve common issues with their USB to serial adapter, ensuring smooth and reliable operation.

U.S. Converters LLC - Serial Data Communication

Monday, October 14, 2024