Serial port programs

Serial port programs and general information:

All Excitron Controllers are very versatile and fast, and they give you many modes of operation.  Our factory settings work fine for some customers.  If you want to make changes, you will need a serial port program running on your computer for setting the parameters for motion and for configuration.  After you have set the Motion Profiles for your application and use, the computer or smart phone is no longer needed, if you choose.  Please browse the Documentation link, or most any product web pages, for the manual and other details for how the Controllers can best fit your project or product. The X Controller has 2 TTL (3.3v logic) serial ports (except 25mm motor controllers and smaller only have 1 TTL serial port), one named CNC and the other CNC2. The CNC port automatically echoes characters while the CNC2 port does not echo characters.  If you wish to use our CNC Gcode ExROS, then both serial ports are auto-configured.


As for your computer programs, please call Bill Gates for advice and friendly service.  Many years ago I met and shook hands with Bill Gates, because he was admiring my award-winning Adam and Eve Game Paddles.  Bill Gates would have done better if he had purchased my game paddles, oh well.

For Android cell phones, we strongly recommend a new serial communication app named Serial USB Terminal by Kai Morich.  Download and install this app by using Google Play Store.  Works well with our USB-TTL-3pin adapter. This app is so good, do not even try others.  It also works with Arduino with CDC driver.  The Settings tab is intuitive and easy to set for 115,200 baud, no parity, 8 data bits, 1 stop bits.  You should also set:

  • Display mode =  Text
  • Font size = 12
  • Show connection messages
  • Newline = none
  • edit mode = Text
  • Local echo = off
  • Clear input on send = ON

We include a free USB adapter for some android phones, not all android phones work.  You could try this adapter from Amazon: USB adapter.

The Excitron Controllers transmit at 115,200 baud. Most controller calculations occur in the time frame of a single character, which is 86.8 useconds.  Actually, most commands are handled within a single bit of 8.68 useconds, then it goes to sleep while the remaining 9 bits come in!  We insert an extra stop bit, 11 bits total, which is 95.5 useconds per character, because all other equipment is slow. This serial response speed is much faster than a 5 GHz PC due to Bill Gates sluggish software.  Even Arduinos, smart phones, and Chrome notebooks are much much slower than Excitron Controllers.

They are so fast that 99% of the time, 96% while the motor is running, the Controller is sleeping.  This saves huge amounts of energy, ideal for battery power systems.  No other controller runs with as little as 1-2ma typical amperage, yet is faster than any other computer in the world!  Grasp this!  Google, IBM, Apple, Xerox, and many other companies want this technology.

So marvel and enjoy the tiny motor controllers, knowing they are also the most powerful anywhere--100 amps!

  • For PCs, Realterm <= download (recommended) is a very sophisticated terminal program, yet relatively easy to use.  It has many interesting features, and uses USB virtual serial ports.  Plug in the Excitron USB adapter prior to starting Realterm.  All details are on this website:  The zipped download file is safe.
    • Only the Display and Port tabs require your attention.
    • On the Display tab, best display is the 2nd ASCII, and you can change the Terminal Font to Courier, which nicely displays the characters from the Excitron Controller.
    • You can change the rows and columns, we suggest 40 to 60 rows, depending on your screen size.
    • Definitely click Scrollback, and type 4 into the little scrollback window, to make it 4200.  too high a number causes Realterm to "quit".
    • Ignore all other items.  Ignore status lights.
    • On the Port tab, the Baud must be 115,200.  You must change baud and Port number each time you start Realterm, that is why it is nice to change your desktop icon, see below.
    • In the Port white line window, click the down arrow to see all available ports.  Windows does not tell you which port is which.   Hopefully you know your computer and can tell.  don't select 1, 2, 3 , 4 server:telnet, or any 127....  Your number is usually between 5 and 20.
    • Click large Change button to the right of the Port line window.
    • The default values are fine for all other items.
    • Move to the large black window, click anywhere, that activates the terminal window.
    • Type I for information.  You should see:  Excitron ExROS v5.xx ...
    • If you don't see this, some thing is still not set up properly, contact us for help.  It is important to mention the difference of:
      • whether you see your typed characters echoed, but the Controller/motor does not do what you expect.
      • or you see nothing when you type.
      • Some companies put a lock on Windows, which prevents new USB devices to be installed.  contact your computer people and have them install the USB software driver.
      • in Windows Start =>  Computer Management => Device Manager, => Ports (COM & LPT), you should see Prolific USB-Serial Comm Port (COMxx).  If you do not see this, get computer help because the driver is not installed.
    • You can change your desktop icon (Properties) with:  ...\realterm.exe "baud=115200 data=8N1 rows=40 port=12.
    • For the port number, set it to what is set for your PC.
    • A nice feature is ability to send text files for controlling the Excitron Controller.  We use hundreds of text files for testing and running.
    • On the Send tab, in the Dump File to Port, click ... to select your txt file.  Your txt file has exactly what you would type; remember, no carriage returns is best--ok since they are ignored.  Change the Delays to 10-30 msecs and line delay to 10-120 ms, depending on what commands you are sending.
    • If you send G, g, or S, your time delay must be longer than the time to run.  Often this is not practical.
    • If Realterm had an easy conditional wait statement, example:  wait until the  >  character is sent, then you would have a complete automation system without writing any code!
    • Realterm has more advanced features on control, see Command Line Parameters.
    • Occasionally RealTerm loses its own USB/serial control, and may cause other USB devices to need to be re-inserted.  Realterm is much better than windows comms ocx.


  • Putty is simple and works fine.  Baud and serial port must be selected each time (not saved).  Able to use USB-RS232 port adaptors which have a virtual serial port, such as our USB-RS232 adaptors.
  • Telix is a reliable and sophisticated terminal program, with many interesting features.  Telix runs as an old DOS program in Windows, except Windows7 and later, and it does not use USB virtual serial ports.
  • Prolific windows USB driver (4.1MB) is only needed if your windows does not have a Prolific USB driver, most windows versions have it.  Visit for more information, and drivers for Linux, Apple, CE, and Android.  The Prolific chip is PL2303 HXA or HX.  Windows8 requires a different method to use these USB adapters.

Excitron uses the new PL-2303TA chipset, which supports all windows versions.
The older PL-2303HXA chipset can be made to work well.  It is not simply supported under Windows 8, as indicated on the manufacturer's driver download page:  Windows 8/8.1 are NOT supported in PL-2303HXA and PL-2303X (End-of-Life) chip versions.  Although Windows 8 automatically installed the driver for the module, the installation was not successful with an error message "..code 10: and "A device which does not exist was specified." shown inside Device Manager.  The Excitron USB PL-2303HXA adapter works fine on Windows XP or 7.
Windows 8 requires the use of signed drivers, which is irrelevant since the Prolific driver is signed.  In any case, the requirements of signed drivers on Windows 8 can be disabled by using the following BCDEDIT commands:
bcdedit.exe -set loadoptions DISABLE_INTEGRITY_CHECKS
bcdedit.exe -set loadoptions TESTSIGNING ON

Apparently it is a driver problem that prevents the PL-2303HXA chipset from working on Windows 8, and not a chipset problem.

The solution is to use an older 2008 driver file (not the driver installer provided by Prolific) downloadable from:

Prolific w8 64 USB driver by using 2008 version ser2pl64.sys.
Prolific w8 32 USB driver by using 2008 version ser2pl.sys.
Prolific w8 USB driver by using 2008 version
Prolific w8 USB driver by using 2008 version ser2pl.inf.
Prolific w8 USB driver by using 2008 version ser2pl.PNF.

Install drivers by placing the file in a directory you choose, then go to Device Manager -> Right click on Prolific-to-Serial Comm Port and select Update Driver Software….  Choose to install the driver manually.  Select Prolific USB-to_Serial Comm Port version model [10/27/2008] from model list and click next.  When prompted, click "Browse my computer for driver software", select the driver's INF file, choose "Let me pick from a list of device drivers on my computer", and select the Prolific driver version 3.3.2 which was created in 2008 (not the latest version).

With this manual selection, the driver will be installed properly on Windows 8 and a new COM port will be added under the Ports (COM & LPT) section in Device Manager and can be used from any terminal program.

These are provided only as a convenience, and no software support is available by Excitron.  You can web search for other serial terminal programs.

See Change by text file link for how to change Motion Parameters easily by sending a text file.

Hyperterminal is free and comes pre-installed with Windows, except for Vista and later.  Hyperterminal works fine most of the time, but will sometimes lose sync with the hardware serial port, and is a little unreliable.

Excitron welcomes your suggestions for other excellent and working serial port programs.

Here is a untested doc to help you with your own serial port C program.

Here is a successful serial program submitted by a happy customer years ago C+ text file to also help you with your own serial port C program.

© Copyright 2023 Excitron Corporation All Rights Reserved.
© Copyright 2023 123ez.Biz All Rights Reserved.
Shopping Cart Powered by 123ez.Biz
Site Map Excitron Corporation

© Copyright 2023 Excitron Corporation All Rights Reserved.
© Copyright 2023 123ez.Biz All Rights Reserved.
Shopping Cart Powered by 123ez.Biz
Site Map Excitron Corporation