Hello All, I'm working on a RTDM driver for a PCMCIA DAQ card. I have already implemented all the basic infrastructure, some ioctls for setting the sampling rate and interrupt sources and have also implemented the interrupt handling (there is some issues with the irqs that I might ask about later). My question is how to best give the data from the driver to the user space data acquisition program. Should I allocate some kernel space and mmap it to the user address space and then use a signal of some kind to inform the user space application when the space is half full ? Any suggestions how this is best done are welcome.
Also I'm using now a clock on the DAQ card to trigger an interrupt at which I read the samples of the card. The card itself (ancient) has only a very small FIFO and I also want to do some DIO on the PCs parallel port for each sample that I read from the DAQ card, so thats why I decided for this design. Would it be better to use a timer from xenomai to do the sample clocking rather than an irq generated by the clock on the DAQ card (performance or otherwise) ? Thanks for your comments, Thomas _______________________________________________ Xenomai-help mailing list Xenomai-help@gna.org https://mail.gna.org/listinfo/xenomai-help
