Computer Control of Chemyx Syringe Pump

Most computer operating systems (e.g., Windows, macOS, Linux, etc.) have built-in terminal programs that can be used to send the commands that run the pump. On Windows XP and earlier operating systems, HyperTerminal can be used to control the syringe pump procedure. On macOS and Linux the screen command in the built-in Terminal app can be used to control the pump. There are also numerous third-party programs for serial connections that exist for each operating system that may provide easier use and more features. Because HyperTerminal was removed in the more recent versions of Windows, a third-party program (e.g., TeraTerm) will be necessary to connect with computers running Windows Vista and later.

Here is a list of some third-party programs that can be used in the syringe pump connection procedure:

Application Operating System(s) Cost
TeraTerm Windows Free
PuTTY Windows/macOS/Linux Free
ZTerm macOS Free
Serial macOS Paid
HyperTerminal Windows Paid
ZOC Windows/macOS Paid
Realterm Windows Free
CoolTerm Windows/macOS/Linux Free
CuteCom macOS/Linux Free

In addition to these terminal programs, the LabVIEW and MATLAB software packages provide serial connection capabilities that allow users to programmatically control the pumps.

We developed a LabVIEW™ Driver for Chemyx Fusion Syringe Pumps, a freeware that helps you interact with Fusion Series Syringe Pumps (Both VI Package Manager and Source code are available).


Regardless of the operating system being used, the program controlling the serial connection should use the following settings procedure to connect to the syringe pump:

Setting Value
Baud Rate* 9600 or 38400
Data Bits 8
Parity None
Stop Bits 1
Flow Control None

* The baud rate setting for the serial connection must match the baud rate set in the pump settings GUI for the Fusion and OEM systems. Generally, the pump should be set to use the higher baud rate (38400) if a USB-only connection is used. However, if a DB9-only or USB-to-DB9 connection is used, the baud rate must be set to 9600. This means that Nexus and Nanojet systems should always have this value set to 9600. Typically, if the baud rate is not set correctly, there will be garbled or no response to any commands.

Procedure for Connecting the Syringe Pump Using screen in macOS and Linux

Both macOS and Linux have the capability of connecting using the built-in Terminal application and the screen command. These instructions assume that the pump is connected to a USB port of the computer.

  1. Ensure that the pump is plugged into the USB port of the computer using either the USB-only cable (Fusion/OEM only) or the USB-to-DB9 adapter (any pump).
  2. Power on the pump.
  3. Check for connected USB devices using the following command:
    ls /dev/tty.usb*

    USB Connected to Fusion 200


    This should return a list of all paths for the devices connected by RS232.

    RS232-connected to Fusion 200

    For example, this command could return the following:


  4. To connect to the pump, use the screen command with the path associated with the connected pump and the baud rate. For example, in the case of the pump in Step 3, which is connected by a USB-only cable, type the following into the Terminal window:


    screen /dev/tty.usbserial-A600AQM6 38400
  5. Upon executing the screen command, the terminal window will go blank. Press the Return key a couple of times. If the connection failed, the terminal window will return to the command prompt. If the connection was successful, a message about an unrecognized command may pop up. Try typing “help” in the terminal. If successful, a list of RS232 pump commands should show up. A detailed description of our RS232 commands can be found here.
  6. DO NOT UNPLUG THE CABLE or CLOSE THE TERMINAL WINDOW BEFORE QUITTING screen. Serial connections need to be properly closed first. To close the connection, press the following keyboard commands:
    1. Ctrl-A
    2. Ctrl-\ (There should be a message at the bottom of the terminal about quitting)
    3. Press the y key to confirm.
  7. Only disconnect the serial cable after quitting the screen command.

Note: Mistakes in typing typically can’t be corrected using Backspace. Instead, users should just enter the incorrect command, and start typing the correct command again.

Procedure for Connecting the Syringe Pump Using TeraTerm in Windows

This syringe pump procedure is coming soon!


For a list of the RS232 ASCII commands, please see our Serial (RS232) Commands article.

Have any questions or comments about this article? Fill out the form below and we'll get back to you as soon as possible!

Privacy & Terms

By choosing "I agree" below you agree to Chemyx Inc Terms of Service. You Also agree to our Privacy Policy, which describes how we process your information.