zio readme: >> + Ctrl: version 0.2, trigger timer, dev zzero, cset 0, chan 2 >> + Ctrl: seq 102, n 4, size 1, bits 8, flags 01000001 (little-endian) >> + Ctrl: stamp 4066.519285605 (0) >> + Data: 60 61 62 63 Jonathan Cameron: > Interesting approach to meta data handling. It's kind of 'partly' out > of band as it can apply to large chunks of data. Exactly. Then, you can ignore the metadata if you want. It's like having a line of packed food, with detailed labels. You can read the label before getting each content blob, or just read the blob and discard the label. Or you can pass everything to someone else, for off-line handling. We are aware there is a serious overhead if blocks are small, but the use case is different, as said. > How does it map if you have triggers causing single captures from each > channel? I would imagine you will then store a whole meta data set per > sample? Yes. Worse: csets are acquired (or output) concurrently, so there's one control structure per channel (actually, gain and offset may be different in each channel, so there's a reason). But when blocks are acquired by a hardware card with 256MB of internal memory and then transferred in a single DMA burst for offline analysis, then the overhead is negligible and I see an advantage in simplicity. Actually, we are considering a buffer that reassembles samples, returning bigger blocks on demand, so we get rid of some of the overhead. But that's more a stress-test for the buffer concept than for real use cases. Sure we lack any in-kernel users and don't want to have them in the future, that's helping us a lot. > I know this isn't your use case, but I'm currious to see where > the overlap lies between this and IIO as you can imagine! Yes, we are too. Federico has an ad7888 driver working, both for IIO and ZIO (and Comedi, but that's out of the game already), and we are going to write for a few more IIO-supported devices. In this way we both validate (or not) our design and compare with IIO. Thank you for your feedback, both here and in the off-list email. /alessandro -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
