how to read/write to ports

This is a discussion on how to read/write to ports within the C Programming forums, part of the General Programming Boards category; hello i am trying to read/write a value to a port (240h for example) but whenever i use inportb() or ...

  1. #1
    Registered User
    Join Date
    Sep 2001
    Posts
    1

    Unhappy how to read/write to ports

    hello i am trying to read/write a value to a port (240h for example) but whenever i use inportb() or outportb() my compiler (bloodshed DEV++) flags it as a reference as an undefined function. i have included the stdio.h, conio.h and dos.h files but still nothing. my sample code is:

    #include <stdio.h>
    #include <conio.h>
    #include <dos.h>

    int main()
    {
    int inportb();
    int result;
    while(1)
    {
    result= inportb(0x240);
    printf("Result is %d",result);
    }
    rteurn 0;
    }

  2. #2
    Guest Sebastiani's Avatar
    Join Date
    Aug 2001
    Location
    Waterloo, Texas
    Posts
    5,708
    Don't know for sure.

    But sometimes, believe it or not, just re-ordering the #include files does the trick! I've had a similar problem solved this way.

    It's a long shot, but...
    Code:
    #include <cmath>
    #include <complex>
    bool euler_flip(bool value)
    {
        return std::pow
        (
            std::complex<float>(std::exp(1.0)), 
            std::complex<float>(0, 1) 
            * std::complex<float>(std::atan(1.0)
            *(1 << (value + 2)))
        ).real() < 0;
    }

  3. #3
    Guest Sebastiani's Avatar
    Join Date
    Aug 2001
    Location
    Waterloo, Texas
    Posts
    5,708
    BTW, in my system, Win '98, Bloodshed Dev compiler, "inportb" for instance, is referenced in WAVE.h ...
    Code:
    #include <cmath>
    #include <complex>
    bool euler_flip(bool value)
    {
        return std::pow
        (
            std::complex<float>(std::exp(1.0)), 
            std::complex<float>(0, 1) 
            * std::complex<float>(std::atan(1.0)
            *(1 << (value + 2)))
        ).real() < 0;
    }

Popular pages Recent additions subscribe to a feed

Similar Threads

  1. condition variable on read/write locks
    By ShwangShwing in forum C Programming
    Replies: 3
    Last Post: 04-29-2009, 09:32 AM
  2. virtual ports
    By royuco77 in forum Networking/Device Communication
    Replies: 5
    Last Post: 07-02-2005, 10:33 AM
  3. Control of ports
    By Blip in forum Networking/Device Communication
    Replies: 1
    Last Post: 05-02-2005, 09:04 AM
  4. Controlling ports
    By lockpatrick in forum Linux Programming
    Replies: 2
    Last Post: 06-09-2002, 11:58 AM
  5. Accessing Ports
    By Thantos in forum C Programming
    Replies: 6
    Last Post: 09-13-2001, 06:01 AM

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21