[Subject Prev][Subject Next][Thread Prev][Thread Next][Subject Index][Thread Index]

Re: interacting with serial driver



On Fri, 9 Jun 2000, Kedar Patankar wrote:

+ > Well, the case is, i want to do, what "open" or "write" or "read" does at
+ > the lowest level, just above the driver.
+ 
+ At the very core "open" just turns on the DTR on the serial port.
+ "Write" essentially just does a outb(SERIAL_DATA_PORT) and a status check,
+ and "read" is tricky. It will block you till enough chars are available
+ (depending on whether you have non-blocking mode set in "open"), and when
+ the serial interrupt occurs the driver will actually read the chars and
+ put them in the buffer. Eventually waking up your prog when enough are
+ accumulated.

While that is true, i need to do that myself, w/o relying on "open" etc.
:( for some reasons. Also, i am not doing this at the user level, but in
kernel proper.

Yeah, writing my own serial driver is another option, but again, due to
certain restraints, i _have_ to use the underlying one :(

Sharad.