585,991 active members*
5,740 visitors online*
Register for free
Login
Results 1 to 3 of 3
  1. #1
    Join Date
    Sep 2007
    Posts
    2

    Strange serial comms issue

    Hi all,

    Any chance you lot can help with this problem?

    I'm sending data from a UART onboard an FPGA to COM1 on my XP desktop. It's straight forward, no handshaking etc, 115200 baud communication.

    Using MTTTY, I can receive characters sent to the COM port if I disable all flow control options, as expected. However, if I try to receive data with Hyperterminal (again with no flow control), I get nothing at all. I also get nothing if I use the Windows API stuff through C++.

    I guess that the same problem is affecting my C++ code and Hyperterminal. I need to eventually get the C++ stuff working, so if anyone can suggest why MTTTY works but Hyperterminal doesn't, I'd be very grateful.

    Many thanks,
    TLS

  2. #2
    Join Date
    Mar 2005
    Posts
    1498
    070926-1641 EST USA

    TLSupper:

    The problem with high level languages is that you have no idea what is going on as a result of your simple command.

    Maybe MTTTY directly accesses the UART.

    Try setting the PC UART FIFO to disable in device manager and use hardware handshake with your program or HyperTerminal.

    .

  3. #3
    Join Date
    Sep 2007
    Posts
    2
    Hi gar,

    Thanks for the suggestion. It turns out the problem was something to do with the cable - I was worried that Hyperterminal might be looking at the control lines so I built a cable with only ground and TX. It works a treat.

    Cheers,
    TLS

Similar Threads

  1. Mazatrol M Plus to PC Comms
    By broby in forum Mazak, Mitsubishi, Mazatrol
    Replies: 13
    Last Post: 05-01-2007, 11:45 AM
  2. Wireless Comms to Mazak
    By bean79au in forum Mazak, Mitsubishi, Mazatrol
    Replies: 1
    Last Post: 10-02-2006, 09:49 AM
  3. Help with selector switch wiring issue (***actually a motor issue***)
    By BEDFORD in forum Charter Oak Automation Support Forum
    Replies: 7
    Last Post: 04-07-2006, 09:19 PM
  4. More Comms problems
    By sleepless1 in forum Mazak, Mitsubishi, Mazatrol
    Replies: 2
    Last Post: 10-28-2004, 07:46 PM
  5. Default Comms Program
    By Rekd in forum Mastercam
    Replies: 9
    Last Post: 06-12-2003, 02:29 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •