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iOptron USB to RS232 converter

iOptron USB to RS232 converter

by iOptron
SKU IOP-8435
$28.00 USD - $28.00 USD
$28.00 USD
$28.00 USD - $28.00 USD
$28.00 USD
Price Match Policy!
  • Connects iOptron mounts with RS232 ports to modern computers via USB
  • Enables firmware updates for hand controllers and main boards
  • Allows for direct PC control using planetarium software and ASCOM drivers
  • Official iOptron accessory
2 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • iOptron USB to RS232 Converter

    The iOptron USB to RS232 converter is the essential link between your iOptron mount and a modern computer. As laptops and desktops have phased out legacy serial ports, this adapter provides a reliable data connection through a standard USB port, enabling critical communication for firmware updates and advanced computer control.

    Essential Connectivity for iOptron Mount Firmware and PC Control

    This converter is for mounts and hand controllers with an RS232 serial port, such as the iEQ45 Pro, where it is used for firmware updates and computer control. Using the correct, tested hardware is critical for preventing communication errors during the update process, which could otherwise render a mount inoperable. Beyond firmware, it unlocks the ability to control your mount directly from a PC.

    By connecting your mount to a computer, you can leverage ASCOM drivers to interface with popular planetarium software like Cartes du Ciel, Stellarium, or TheSkyX. This allows you to command your mount from a rich visual interface, replacing the hand controller for object selection and slewing, and is a foundational step for automated imaging sequences.

  • Why do I need the iOptron USB to RS232 converter?

    Most modern computers no longer include the 9-pin RS232 serial port that the serial cable of RS232-equipped iOptron mounts and hand controllers plugs into for firmware updates and direct computer control. The iOptron USB to RS232 converter bridges this gap, allowing you to connect your mount's serial port to a standard USB port on your laptop or PC.

    Can I use a generic USB-to-serial adapter with my iOptron mount?

    While some generic adapters may work, many use chipsets with unreliable drivers that can cause connection drops or data corruption, especially during a critical firmware update. Using the official iOptron USB to RS232 converter is highly recommended as it has been tested to ensure stable, error-free communication with their mounts and software.

    What software can I use with the iOptron USB to RS232 converter?

    This converter enables you to connect your mount to a wide range of software. Primarily, you will use it with iOptron's own firmware upgrade utility. For telescope control, it works with any software that communicates via the ASCOM platform, including popular choices like N.I.N.A., Sequence Generator Pro, Cartes du Ciel, and Stellarium.

    How do I use this converter to update the firmware on my iOptron CEM40 mount?

    On a CEM40 with the 8407+ hand controller, plug the RJ9 end of the serial cable (RS232 to RJ9, supplied with the #7400A series) into the serial port on the hand controller, and the RS232 end into this converter. Plug the converter's USB end into your computer. After installing the FTDI VCP driver, you can run the iOptron Upgrade Utility software to load the new firmware onto the hand controller. The mount's main board is upgraded through its own USB port, and a CEM40 with the 8410 hand controller (no RS232 port) needs no converter.

    Does the iOptron USB to RS232 converter require special drivers?

    Yes. Like most USB-to-serial devices, it needs a virtual COM port driver. iOptron's manuals point to the FTDI USB to RS232 VCP driver from ftdichip.com rather than a driver on iOptron's site.

    My new laptop only has USB-C ports. Can I still use this iOptron converter?

    Yes. Use a USB-C adapter or hub that matches the converter's USB plug.

  • Kind USB to RS232 converter (FTDI chipset)
  • iOptron Warranty