Simple device driver

QNX Newsgroups (Archives) qdn.public.qnx4
1

Hi folks,

I need to write a simple device driver to write a value to an I/O port to
implement a watchdog.
I’ve read the excellent section in Rob Krten’s book about how to write a
resource manager but this focuses solely on the client interfacing and has
no information regarding how to write to the port.
At the moment I can implement a simple driver which receives write
instructions from a client process, etc. but I don’t know what to do to
actually write to the hardware port. I expect that this is pretty
straightforward (if you know how)?

Any advice would be appreciated.

Cheers,

Liam Power.

2

See the on-line help for inp(), inpd(), inpw(), outp(), outpd() and outpw()

  • Richard

“Liam Power” <liam.power@hofmann-ge.com> wrote in message
news:9f2fbh$cmr$1@inn.qnx.com…

Hi folks,

I need to write a simple device driver to write a value to an I/O port to
implement a watchdog.
I’ve read the excellent section in Rob Krten’s book about how to write a
resource manager but this focuses solely on the client interfacing and has
no information regarding how to write to the port.
At the moment I can implement a simple driver which receives write
instructions from a client process, etc. but I don’t know what to do to
actually write to the hardware port. I expect that this is pretty
straightforward (if you know how)?

Any advice would be appreciated.

Cheers,

Liam Power.
\

3

Brown, Richard <brownr@aecl.ca> wrote:

See the on-line help for inp(), inpd(), inpw(), outp(), outpd() and outpw()

Yup, and you need to link -T1 for hardware privity, otherwise the
above functions will cause your program to SIGSEGV.

-David

QNX Training Services
dagibbs@qnx.com

4

Thanks Guys!

-Liam.

“David Gibbs” <dagibbs@qnx.com> schrieb im Newsbeitrag
news:9f34i4$dgv$1@nntp.qnx.com…

Brown, Richard <> brownr@aecl.ca> > wrote:
See the on-line help for inp(), inpd(), inpw(), outp(), outpd() and
outpw()

Yup, and you need to link -T1 for hardware privity, otherwise the
above functions will cause your program to SIGSEGV.

-David

QNX Training Services
dagibbs@qnx.com