On Tue, 1 Dec 2009 19:31:24 +0100 (CET) [email protected] (Karl Hammar) wrote:
> Patrick Shirkey: > > Just to recap. These are the points that have been discussed so far. > > ------------------- > > Physical Size > > ------------------- > > > > http://www.rittal.com/products/ArtikelDatenblatt.asp?ArtNr=1360500&lang=GB > > > > 600 mm x 600 mm x 350 mm > > No, this is where I will put my system into. The actual "computer" > would be much smaller. I'm planning on something like > > h: ~240, w: <200, d: < 200mm > > But I don't think you should have to abide to that. > > +++++ At this stage, I'd just say whatever is easiest to work with. Shrinkage and prettifying can come later! > For the "soundcard" part, it might be more useful if we instead talk > about interfaces. > > With SPI, we are free to "attach" many different cpu-cards, it's just > clock, data out, data in, and a few chip select lines. And we can > potentially get 10-20 channels at cd quality. > > With faster i/o, we can use the cpu's memory interface, or > some ordinary bus like pci or pci-x. > > I'm not for pci or pci-x at this point, since that would be for me a > totally different project. Unless, of cause, someone else takes care > about the "bus" part, and I and others do the ad/da and analog part. > > With spi or the memory bus, we cannot use an ordinary pc --- to bad. > But we could use the atmel network card mentioned a few lines below, > or the card I will eventually build, or some card someone else provides > source to. PCI is on the way out and PCI-x seems to be rather fluid spi seems more future-proof (in as much as anything can be) > > --------------- > > Hardware > > --------------- > > No decision has been made on the viability of designing a board from > > scratch. > > I will probably do everything from scratch, but given good and > sensible interfaces card<->card, one could possible use "any" > suitable cpucard. > > > - You have access to this board for development/testing: > > http://www.atmel.com/dyn/products/tools_card.asp?tool_id=4102 > > Ack. > > > The aim is to provide upto 8 audio i/o ports. > > I don't think we should set an upper limit, instead it would be > interesting to see how many channels the system could support. Very much agree, start simple and see how far we can push it. > I would say we try to make (input and output) > > one desent channel, e.g. 16bits, 44.1/48kHz > one very good channel (if we manage), 24bits 192kHz, to try the limits > > And then see how many we can fit into the system. > > And, would that be an line input, or mic input channel, or > (software) switchable? Initially line only, much easier to get a decent performance. Also there are *lots* of mic preamps out there and everyone thinks theirs is the best :) > Talking about, i/o. Would buttons, leds, relays, linear and rotary > things (what is their name?), etc. be useful ? KISS Status LEDs would be good, but levels should be software controlled, so no need for mechanical switches, Pots, Faders etc. > > Connectivity via Gigabit ethernet. > > I don't think the atmel can do gigabit. Fast ethernet (100Mpbs), > is a more realistic choise unless we switch cpu. Almost everyone has fast Ethernet, so lets stick with that for as long as possible. It's easier to upgrade than downgrade! > > -------------------------- > > Firmware/Software > > -------------------------- > > The device will run Linux OS. > > Audio data transfer will be via netjack using CELT compression. > > Ack. I'll just go with the flow here :) > > ------------- > > Website > > ------------- > > Need to define project vision, setup wiki, git-hub etc... > > Ack. > > I have some readme's at [2], and I will put all my other design files > there. > > Here are some thoughts (extract from [3]): > > The requirements are > . it should run linux > . developed with open source tools, current choise is gEDA > . expandable, you be able to easily add e.g. 8 D/A ports, 32 DIO etc. > preferably hotpluggable > . electrically rugged and EMC safe > . easy to make and build yoursalf, preferable double layer card > . the components should be available/purchable for a normal hardware hacker > . the should not cost to "much" > . no card edge connector > > It seems that my "archetectural" choises are > . a single board computer > . a stackable system like pc104, pico-itxe or arduino > . a card frame system, either > - whith a backplane bus, like VME or CompactPCI > - or with the "backplane" on the cpu card, the motherboard style like ATX > > The one which is easiest to expand is the card frame system with a backpland, > I will make my first try with that. Pretty much ticks all the boxes for me. -- Will J Godfrey http://www.musically.me.uk Say you have a poem and I have a tune. Exchange them and we can both have a poem, a tune, and a song. _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
