Single Port USB to RS-232, RS-422 and RS-485 Serial Adapters
Features
- Add a RS-232, RS-422 or RS485 serial port to any USB equipped computer
- Data transfer rates up to 920K baud
- Built in six foot cable
- Plug-n-Play allowing quick connect/disconnect whenever you need an additional serial port
- Ideal for use with portables and laptops
- No available board slots needed
- RoHS Available. Please contact us for ordering information

These USB adapters are intelligent modules which provide a cost-effective solution for transferring high-speed asynchronous serial data over USB. The adapters provide easy connectivity between the computer and standard communication ports or remote serial devices. No PC reconfiguration, assignment of IRQs, or jumper settings required. The adapter will be recognized as a USB to Serial Adapter and install in the system as a standard COM port.
SYSTEM REQUIREMENTS
- A PC with a minimum of a 75MHz Pentium, or equivalent
- A minimum of 16M bytes of RAM
- One available USB type port compliant with USB1.1
- Drivers are included on our software master CD that normally ships with ACCES hardware. Supported Operating Systems: Windows 98/SE, 2000, Me, XP, Linux - built-in to kernel 2.4.0+, MAC OS/8.2 and higher (including X). Driver information is subject to change. Check with ACCES for updated driver information.
CONNECTIONS TO SYSTEM
The USB adapter is equipped with a USB cable and a USB type A connector for connection to a computer USB port and a male DB-9 for connection to a RS-232 or RS-422/485 equipped data or communication terminal. The USB adapter automatically configures with Windows Plug-n-Play functionality. This means that once you plug the device into a computer, Windows will automatically detect the device and launch an installation wizard.INDICATORS
One two-color LED indicator displays transmission of data (green) or reception of data (orange) of the serial port for easy verification of operation.Specifications
- Communication speed: 300 to 920K baud
- I/O Addressing: USB Plug-n-Play - auto selection
- 384 byte receive buffer / 128 byte transmit buffer for high data throughput
- USB Bus Powered (No external power supply required)
- USB 1.1 (can be used with USB 2.0), UHCI / OHCI Specification Compliant
- Uses FT8U232AM dedicated USB UART
- Full hardware assisted or X-On/X-Off handshaking in RS-232 mode
- Supports Auto-RTS in RS-485 mode
- Interface Connector: DB-9, Male
Ordering Guide and Modes of Operation:
- USB-232: Only RS-232
- USB-422: RS-422 Full Duplex (4-wire)
- USB-485: RS-485 Half Duplex (2-wire). Connections between +Tx and +Rx pins 2 & 9 and between -Tx and -Rx pins 3 & 1 have to be made in the external cable.
- USB-422/485:
- RS-422/485 Full Duplex (4-wire). May need external bias on +Tx and -Tx if this is not provided by another device.
- RS-485 Half Duplex (2-wire) with local echo. Connections between +Tx and +Rx pins 2 & 9 and between -Tx and -Rx pins 3 & 1 have to be made in the external cable.
Regulatory Compliance
- This product is designed to be in full compliance with CE requirements.

| Model | Price (USD) |
|---|---|
| USB-232 | 39.00 |
| USB-422 | 89.00 |
| USB-485 | 89.00 |
| USB-422/485 | 109.00 |
Available Reference Manuals
- View / Download the USB-232-CONV Manual (.PDF)
- View / Download the USB-422-CONV Manual (.PDF)
- View / Download the USB-485-CONV Manual (.PDF)
Available Software Downloads
Available Datasheets
- View / Download the USB-232-CONV Data Sheet (.PDF)
Further information about available ACCES Software:
- Drivers And Operating Systems
- What drivers and other support we provide for various operating systems.
Setup Programs, Samples, And Utility Software- A description of the software package that comes with each ACCES card.
Redistributing Windows Drivers- A list of ACCES drivers and the files that compose them under different versions of Windows, so you can easily redistribute ACCES cards and drivers.
Custom Software Services- A description of some of our custom software offerings. Did you know we offer free programming services to qualifying customers?









