pci tv card

Chris Caudle chris at chriscaudle.org
Thu Nov 14 18:35:04 UTC 2002

On Thursday 14 November 2002 10:05 am, shanehelms at eircom.net wrote:
> couple of questions:
> 1. is there any concept of kernel and user mode in rtems or is it all in
> kernel mode?

Flat memory model.  An application on RTEMS is a single process, which may 
contain multiple threads (that is, all the threads have access to all the 
memory), and no memory protection or virtual memory is used.

> 2. im lost with the concept of region and partition, how can
> i read/write/copy to memory (ie something like memcpy function in linux)

I think the C library in RTEMS contains a memcpy function.
I had to uninstall my RTEMS tools temporarily to make some space, so I can't 
check myself right now.  Anyone else know for sure?

> 3. how can i write/read register value of a pci device ?

You find out where the device registers are mapped, and just write and read 
to those locations using pointer indirection.  On a PC386 BSP, there are 
some functions which call the PCI bios on the machine to let you find the 
base address of the card.

Chris Caudle

More information about the users mailing list