How to access the parallel port

[falcon eyes]

Hi Every body
I'm using MS Studio 2008 On Operating System VISTA Ultimate, i tried to write a program for reading the status of the parallel port and that what i had made
1-Create a MFC application and called it "ParallelPort"
2-I added a checkBox and associated it with the bool variable "m_Pin10"
3-i included the <conio.h> at the begining of ParallelPortDlg.cpp
4- i created a Fn called void UpdatePins(void) and has the following body
int reg;
reg=_inp(0x379);
if((reg&0x40)==0) m_Pin10=0; else m_Pin10=1;

5-I created a button to call the Fn UdatePins()

i compiled the program and after running the application and press the button
i get an error message(included as attachment)

is any body know what's wrong with my code,is there other Fn rather than_inp() Fn
pls advice

[vijayan]

you could try using a hardware access library. eg. WinRing0
http://openlibsys.org/manual/
http://sourceforge.net/projects/winring0/

[Danny]

You can't access the hardware directly in Vista. You need to use a special hardware access library for that purpose, as vijayan said.

[falcon eyes]

thanks vijayan & Danny
i downloaded WinRing0 but didn't know how to use it in my program would you please tell me how to do it

[vijayan]

1. unpack the zip file.
2. read the extracted file manual.chm - section "How to Use"

How to Use 
Common
Put WinRing0.dll, WinRing0x64.dll, WinRing0.sys, WinRing0x64.sys, and WinRing0.vxd 
into the directory where your application's executable file resides.

Visual C++ 2005/2008 
See also sample application. 

Load-Time Dynamic Linking 
Add WinRing0.lib or WinRing0x64.lib to your project. 
Add #include "OlsApi.h" statement to your source file. 
Call InitializeDll(). 
Call the library's functions. 
Call DeinitializeDll(). 
...

3. in manual.chm - section "Core API" read about the functions of interest to uou.
eg. ReadIoPortWord, WriteIoPortWord

[Hack]

There are publications for this product on this site.

http://www.bto.org/software/ipmr/winring.htm

[falcon eyes]

this is my Fn

void CParallelPortDlg::UpdatePins(void)
{
unsigned char reg;
InitializeDll();
reg=ReadIoPortByte(0x378);
if((reg&0x40)==0) m_Pin10=0; else m_Pin10=1;
DeinitializeDll();
}
When i applied the instructions in the manual i got these errors

ParallelPortDlg.obj : error LNK2019: unresolved external symbol "void __stdcall DeinitializeDll(void)" (?DeinitializeDll@@YGXXZ) referenced in function "public: void __thiscall CParallelPortDlg::UpdatePins(void)" (?UpdatePins@CParallelPortDlg@@QAEXXZ)

1>ParallelPortDlg.obj : error LNK2019: unresolved external symbol "unsigned char __stdcall ReadIoPortByte(unsigned short)" (?ReadIoPortByte@@YGEG@Z) referenced in function "public: void __thiscall CParallelPortDlg::UpdatePins(void)" (?UpdatePins@CParallelPortDlg@@QAEXXZ)

1>ParallelPortDlg.obj : error LNK2019: unresolved external symbol "void __stdcall InitializeDll(void)" (?InitializeDll@@YGXXZ) referenced in function "public: void __thiscall CParallelPortDlg::UpdatePins(void)" (?UpdatePins@CParallelPortDlg@@QAEXXZ)

1>C:\Users\Falcon Eyes\Documents\Visual Studio 2008\Projects\ParallelPort\Debug\ParallelPort.exe : fatal error LNK1120: 3 unresolved externals

[vijayan]

add the import library WinRing0.lib (or WinRing0x64.lib for 64 bit) to your project.