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usb to rs232 serial cable

Discussion in '8051/8951' started by Parth86, Sep 11, 2014.

  1. Parth86

    Parth86 Member

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    hello ,
    I want to burn hex code from Laptop to p89v51rd2. but I don't have usb to rs232 serial cable

    laptop -aspire746
    os- window 7
    serial port
    microcontroller nxp89v51rd2
    compiler - keil
    programer software - flesh magic
    com port 1
    baud rate 9600
    interface - none ISP
    max RS232IC

    usb to rs232 serial cable is not available in my place so I used two cable to burn hex code I have driver cd
    programmer circuit +Db9 male connector +db9female connector------cable-----db9 female+db9male--able --- usb port to laptop port

    Q. it will work ? or tell me how to burn hex code
     

    Attached Files:

  2. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    Should work... You seem to have a USB to RS232 converter in your image!!

    Just try it.... It will either work or not.... Just make sure Txd goes to Rxd throughout... Your setup is no different to said cable anyway..
     
  3. Parth86

    Parth86 Member

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    thank you Ian sir


    how to know that my controller and programmer circuit is working correctly

    so I used multimeter I connected 9 v dc battery and I measured supply voltage for microcontroller I got 3.95 vdc and I saw 3.65 vdc for programmer circuit

    so my controller and programmer circuit is correct ?
     
    Last edited by a moderator: Sep 12, 2014
  4. dave

    Dave New Member

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  5. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    Can you show me the schematics of your micro controller
     
  6. Parth86

    Parth86 Member

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    you mean datasheet .at this time I don't have good quality picture. I have image that you gave me in another post
    I have made this connection on bread board .

    I used multimeter I connected 9 v dc battery and I measured supply voltage for microcontroller I got 3.95 vdc and I saw 3.65 vdc for programmer circuit

    look at this code and tell me its correct
    look at this assembly code
    Code (text):
          org 00h

          Setb P3.2              ; Led on
          clr   P3.2           ; Led off
     
           delay:
        mov    R1, #20
        mov    R2, #0
    delay1:    djnz    R2, delay1
        djnz    R1, delay1

       ret
       end  
    hex code
    Code (text):
    :0D000000D2B2C2B379147A00DAFED9FC2224
    :00000001FF

    I tried to burn hex code but I got message reset device in ISP mode now ?
     
     

    Attached Files:

    Last edited by a moderator: Sep 12, 2014
  7. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    Vead. Slightly off topic, but why "No link here" in your breadboard graphic? Is that jumper position acting as an "On/Off"?

    Just wondering...
     
  8. hexreader

    hexreader Member

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    I think I can see why...

    There is 9V to the right of the missing link and 5V to the left. Inserting a link would provide 9V to the ICs, which is much to high.

    I see no connection from lower ground rail to upper ground rail - that might be the problem.

    If the voltage regulator is 5V, and you only get 4V out, either your battery is flat, or there is a fault in the circuitry somewhere
     
  9. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    Yes I drew that circiut for my tutorials.... The breadboard has no connection under the middle... I have used 9v on one side and 5v on the other..

    vead Read through the tutorial as you need a toggle switch to reset the micro to bootloader mode
     
  10. Parth86

    Parth86 Member

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    actually this is not original circuit now I am using 9 vdc and controller get the 4.16 vdc

    I am trying to burn code I am getting message reset device in ISP mode now I think I need reset switch But I don't have reset switch
     
  11. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    Why 4.16v..... The chip surely runs on 5V....

    On the breadboard... Just jumper the pin to ground when bootloading....
     
  12. Parth86

    Parth86 Member

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    I am using 9 v dc for both micro controller and programmer circuit
    I tried
     
  13. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    What programmer ciruit? The micro has a bootloader..... It programs directly through the serial port...
     

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