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RS-232 serial port problem

  1. Mar 6, 2008 #1

    I am using RS-232 connection to may FPGA, and I want to send information from matlap. Whan I set may VHDL program to the defult seting of the RS-232 which have 9600 bit/sec, then may FPGA show the data correctly. but whan I change the VHDL program and the matlap seting to anthor bit/rate,the data is shown wrong. what is intresting is that the old VHDL program with 9600 bit/sec still work which mean the computer still send at the old bit rate.
  2. jcsd
  3. Mar 6, 2008 #2


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    Staff: Mentor

    Sounds like Matlab's changing of the serial port settings is not taking effect. You could manually change the settings in the Control Panel for the PC, perhaps.
  4. Mar 6, 2008 #3
    How do you know that it is still working? The bit rate might be correct but maybe you change the protocol without knowing it ... Double check that you still use the old protocol, and make sure the bits are in the correct order.
  5. Mar 8, 2008 #4
    Hi again
    I discover that not all of the data rate for RS-232 are providen by may PC. but still I have problem. The data that I want to load on may FPGA board is very larg and RS-232 have very low bit rates. May bord is spartan-3 digilent (X3S1000)
    Do you have any other way to load these data from PC.
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