copy to COM in cmd prompt

Posted on 2005-04-11
Last Modified: 2012-06-27

I'm trying to send files to a thermal printer via RS232.  In the manual, it says i can just send these command files to the printer via dos copy with the /b binary switch.  My printer is on COM3..  what is the syntax for copying to a COM port?  i can't figure it out..

thanks - Trevor
Question by:trevorhartman
    LVL 7

    Assisted Solution

    copy filename > com3: /b
    LVL 32

    Expert Comment

    copy filename > com3: /b

    I assume you really meant:

     copy filename com3: /b
    LVL 8

    Author Comment

    thanks all.... when i copy a file to the printer is it supposed to print?
    LVL 8

    Author Comment

    it says 1 file(s) copied, but i was expecting it to print..
    LVL 32

    Accepted Solution

    The most likely problem is that the baud rate (or handshaking protocol) is not matching.

    Do you know what baud rate the printer is expecting?

    If not, try the following command from the command prompt before using the above Copy command:

    > mode com3: 9600,n,8,1
    > copy... etc.

    Also, make sure you have the proper cable (there are at least two types, pins 2 and 3 are crossed over, or not).

    Also, create a very short text file with notepad, say "temp.txt", and try printing that first:

    > copy temp.txt com3:

    This may be obvious, but are you sure that COM3 is the port your printer is connected to? Most PC's just have 1 or 2 serial ports.
    LVL 8

    Author Comment

    great, thanks for your help, i got it working

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Why You Should Analyze Threat Actor TTPs

    After years of analyzing threat actor behavior, it’s become clear that at any given time there are specific tactics, techniques, and procedures (TTPs) that are particularly prevalent. By analyzing and understanding these TTPs, you can dramatically enhance your security program.

    Can I legally transfer my OEM version of Windows to another PC?  (AKA - Can I put a new systemboard in my OEM PC?) Few of us are both IT and legal experts but we all have our own views of Microsoft's licensing rules and how they apply.  There are…
    If your system is showing symptoms of browser hijacks or 'google search redirects' check out my other article ( first and run the tool TDSSKiller ( to get rid of the infection. Once done, and if the …
    Internet Business Fax to Email Made Easy - With eFax Corporate (, you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…
    Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.

    761 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    7 Experts available now in Live!

    Get 1:1 Help Now