use of serial and parrallel port using C

[The Man With The Harmonica]

Hi All,

What kind of commands can I use to control the serial and parallel port of
my pc. I want to use my laptop instead of microcontroller s and write my
software in ANSI C to be used for control purposes of sensors and other
electronic devices.

I haven't done any C for a while now so I would assume my knowledge is that
of a beginner now.

A thousand thanks for any help offered or intended.

Naveed

[Mark A. Odell]

"The Man With The Harmonica" <co************ ****@yahoo.co.u k> wrote in
news:cf******** **@rdel.co.uk:

Hi All,

What kind of commands can I use to control the serial and parallel port
of my pc.

None. ISO C doesn't have any commands nor does it know anything about
serial or parrallel ports. You'll need to ask this in a newsgroup that
programs for the platform you are using, e.g. DOS, Linux, Win32, etc.

--
- Mark ->
--

[Thomas Matthews]

The Man With The Harmonica wrote:

Hi All,

What kind of commands can I use to control the serial and parallel port of
my pc. I want to use my laptop instead of microcontroller s and write my
software in ANSI C to be used for control purposes of sensors and other
electronic devices.

I haven't done any C for a while now so I would assume my knowledge is that
of a beginner now.

A thousand thanks for any help offered or intended.

Naveed

news:comp.arch. embedded

One can use ANSI C to access serial ports and parallel ports
as well as other devices as long as those devices are memory
mapped. Whether the operating system, if there is one, allows
this is a different issue.

However, this code would be platform specific and not portable
to platforms that do not have the same memory mapping.

The technique is to access the hardware devices by dereferencing
pointers. For example, one would assign a pointer to an integer
with the value of the device's address:
volatile unsigned char * Serial_Receive_ Register =
(volatile unsigned char *) 0x40000;

unsigned char Read_Serial_Por t(void)
{
return * Serial_Receive_ Register;
}

Before reading the receive register, one should check that
the status first and also have a design to handle when
nothing has been received.

--
Thomas Matthews

C++ newsgroup welcome message:
http://www.slack.net/~shiva/welcome.txt
C++ Faq: http://www.parashift.com/c++-faq-lite
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alt.comp.lang.l earn.c-c++ faq:
http://www.comeaucomputing.com/learn/faq/
Other sites:
http://www.josuttis.com -- C++ STL Library book

[SM Ryan]

# What kind of commands can I use to control the serial and parallel port of
# my pc. I want to use my laptop instead of microcontroller s and write my
# software in ANSI C to be used for control purposes of sensors and other
# electronic devices.

Depends in part on whether the operating system provides file names for
those devices that you can fopen. For example on unices, you can open
serial ports with file names like "/dev/ttyS0".

--
SM Ryan http://www.rawbw.com/~wyrmwif/
The whole world's against us.

[Dan Pop]

In <6i************ *****@newssvr17 .news.prodigy.c om> Thomas Matthews <Th************ *************** *@sbcglobal.net > writes:

The Man With The Harmonica wrote:

Hi All,

What kind of commands can I use to control the serial and parallel port of ^^ my pc. I want to use my laptop instead of microcontroller s and write my ^^^^^ ^^^^^^^^^
software in ANSI C to be used for control purposes of sensors and other
electronic devices.

I haven't done any C for a while now so I would assume my knowledge is that
of a beginner now.
news:comp.arch .embedded

Since when do PC's count as embedded control systems?
One can use ANSI C to access serial ports and parallel ports
as well as other devices as long as those devices are memory
mapped.
Chapter and verse, please.
Whether the operating system, if there is one, allows
this is a different issue.
If ANSI C supported the feature, the OS would be irrelevant.
However, this code would be platform specific and not portable
to platforms that do not have the same memory mapping.
Then, it wouldn't be code blessed by ANSI C.
The technique is to access the hardware devices by dereferencing
pointers. For example, one would assign a pointer to an integer
with the value of the device's address:
volatile unsigned char * Serial_Receive_ Register =
(volatile unsigned char *) 0x40000;

According to ANSI C, any attempt to use this pointer value results in
undefined behaviour.

The *right* thing is to use the OS interface to the serial port. The
kind of code you're showing belongs exclusively to device drivers and
is highly unlikely to work in userland programs. Imagine what happens
when two programs attempt to access the same port directly, at the same
time (assuming that it would be possible): complete chaos.

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de

[The Man With The Harmonica]

"Mark A. Odell" <od*******@hotm ail.com> wrote in message
news:Xn******** *************** *********@130.1 33.1.4...

"The Man With The Harmonica" <co************ ****@yahoo.co.u k> wrote in
news:cf******** **@rdel.co.uk:

Hi All,

What kind of commands can I use to control the serial and parallel port
of my pc.

None. ISO C doesn't have any commands nor does it know anything about
serial or parrallel ports. You'll need to ask this in a newsgroup that
programs for the platform you are using, e.g. DOS, Linux, Win32, etc.

--
- Mark ->
--

Hi Mark,

I'm using an old Toshiba laptop with win95. I want to use the parallel port
to control some circuits and to read the state of some control lines.
Basically its going to be controlling a four wheeled buggy and I want to do
this using C and through the parallel port.

thanks

Naveed

[Flash Gordon]

On Thu, 19 Aug 2004 16:51:06 +0100
"The Man With The Harmonica" <co************ ****@yahoo.co.u k> wrote:

"Mark A. Odell" <od*******@hotm ail.com> wrote in message
news:Xn******** *************** *********@130.1 33.1.4...

"The Man With The Harmonica" <co************ ****@yahoo.co.u k> wrote
in news:cf******** **@rdel.co.uk:

What kind of commands can I use to control the serial and parallel
port of my pc.

None. ISO C doesn't have any commands nor does it know anything
about serial or parrallel ports. You'll need to ask this in a
newsgroup that programs for the platform you are using, e.g. DOS,
Linux, Win32, etc.

I'm using an old Toshiba laptop with win95. I want to use the
parallel port to control some circuits and to read the state of some
control lines. Basically its going to be controlling a four wheeled
buggy and I want to do this using C and through the parallel port.

So go and ask on a a group for you platform as Mark suggested. Standard
C does not provide you with any way to to what you want and this group
talks about standard C.
--
Flash Gordon
Sometimes I think shooting would be far too good for some people.
Although my email address says spam, it is real and I read it.

[SM Ryan]

# So go and ask on a a group for you platform as Mark suggested. Standard
# C does not provide you with any way to to what you want and this group
# talks about standard C.

Still shooting from the hip and blowing off your own toes. Depending on
the operating system, it may be possible to fopen a device name and
then use stdio to read/write the port.

--
SM Ryan http://www.rawbw.com/~wyrmwif/
Why are we here?
whrp

[Default User]

SM Ryan wrote:

# So go and ask on a a group for you platform as Mark suggested. Standard
# C does not provide you with any way to to what you want and this group
# talks about standard C.

Still shooting from the hip and blowing off your own toes. Depending on
the operating system, it may be possible to fopen a device name and
then use stdio to read/write the port.

Exactly how stupid are you? There is no standard way to do that. There
are only platform-specific ways, and so the person seeking the
information should go ask on a newsgroup dedicated to the specific
platform.

Since you first graced our newsgroup, you've been a fount of bad
information and bad attitude, as well as continuing to use those
non-standard reply delimiters.

Brian Rodenborn

[Flash Gordon]

On Thu, 19 Aug 2004 21:33:23 -0000
SM Ryan <wy*****@tang o-sierra-oscar-foxtrot-tango.fake.org> wrote:

# So go and ask on a a group for you platform as Mark suggested.
Standard# C does not provide you with any way to to what you want and
this group# talks about standard C.

Still shooting from the hip and blowing off your own toes. Depending ^^^^^^^^^ on the operating system, it may be possible to fopen a device name and ^^^^^^^^^^^^^^^ ^^^^^^^^ then use stdio to read/write the port.

You said it yourself, it DEPENDS ON THE OPERATING SYSTEM. Therefor it
needs to be asked in a group dealing with the operating system. If the
OP find it can be done using fopen and friends, then questions can be
asked about the things which can be done in standard C. However, if the
OP knew that was possible then the question would not have been asked.
--
Flash Gordon
Sometimes I think shooting would be far too good for some people.
Although my email address says spam, it is real and I read it.