SCREEN                   Character at Specified Location             Function

 y = SCREEN(row,column[,z])

    Returns the ASCII or color information about a specified screen
    location.

     row,col    Absolute coordinates of a screen location.

           z    If omitted or 0, SCREEN returns the ASCII value of the
                    character at row,col.

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      Notes:    The z argument is valid only in text mode.