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I/o line interface to switches and LED's

naresh rana

Hi all

There are total 6 i/o lines available on controller,
5 switches and 5 LED's are to be interfaced by using this 6 I/O's.No other external IC are to be used,only resistors and similar parts can be used.

any suggestion to achieve this will be appreciated.

rgds
Naresh

  • 0

    You cannot drive a LED directly by a 8051's pin.

  • 0 in reply to Dusan Stan

    "You cannot drive a LED directly by a 8051's pin."

    Oh yes you can - provided that you have carefully read the Data Sheet and verified that the ratings are sufficient.

    You will, of course, still need the normal current-limiting device (eg, series resistor) - see the LED Data Sheet.

    Note that many devices specify a maximum current for each pin and a maximum total for the whole chip - again, read the Data Sheet

  • 0 in reply to Andy Neil

    5 switches and 5 LED's are to be interfaced by using this 6 I/O's.No other external IC are to be used,only resistors and similar parts can be used.

    any suggestion to achieve this will be appreciated.
    I believe this is homework since the solution is dead simple after you think a bit. So, your teacher is trying to "teach you to fish" (think) and you want us to "give you a fish".

    Erik

    PS

    only 5 I/Os are needed for a simple solution, six for an 'elegant'