Raspberry Pi and America, was Re: ST-506/412 to IDE/ATA/SCSI/? adaptor

On Jun 27, 2012, at 4:07 PM, Tony Duell wrote: Well, for all it's worth, there *is* a schematic... http://www.raspberrypi.org/wp-content/uploads/2012/04/Raspberry-Pi-Schemati… The hardware documentation is basically in the form of a Wiki, which I guess is how people handle documentation when they don't really want to write documentation themselves (sometimes, it works; I'd call the RPi Wiki a semi-success, because it's still really poorly organized). There is a datasheet, though, that covers most of the actual peripherals except for the video portion and a few others: http://www.farnell.com/datasheets/1521578.pdf As you've noted, it's somewhat redacted. To be honest, it's a lot better than what I expected, given that it's a Broadcom part. We have to deal with Broadcom parts at work from time to time, and getting datasheets out of them is worse than pulling teeth. For one thing, we're a small consulting house, so they typically won't even deal with us until we get our larger customers involved. Then their lawyers make us sign a contract in blood promising our firstborn children if we ever let their SENSITIVE TRADE SECRETS (i.e., register maps) into the hands of their sworn enemies. After all that, they wouldn't even give us a damned PDF; one person got a hardcopy in a binder (because apparently copying machines no longer exist?) to share amongst a team of 5 people. So yeah, while it's not *ideal*, it's a lot more than I ever expected the cyborg ultra-lawyers at Broadcom to approve. Well, yeah. The entire budget of the project is basically built on volume, since that drives the cost of silicon down. Broadcom won't even deal with you unless you're planning to make tens of thousands of units (or have REALLY deep pockets, like one of our customers). I think the entire release of the board was made possible only because one of the founders works at Broadcom and co-developed the SoC that serves as the CPU. So yes, if they used a commodity chip that didn't have the RAM stacked up on it, that would drive the cost up and they'd no longer be able to sell the base model for $25 (or ?15 or whatever it is over there). That's a tradeoff, I suppose; for a device that is priced essentially at the "expendable" price point, it's one I'm willing to take. I agree, I wouldn't want to design anything around it that wasn't a one-off. I don't think that was ever the intention of the whole project (it was to get computers in the hands of kids, which it seems to be doing well enough and will probably do better once they reach capacity). You can still make some pretty cool stuff, though. I'm not trying to persuade you to go out and buy one, because that would be silly (I doubt you'd use it that much, since you don't have most of the peripherals to attach to it), but I think in the scheme of what it's meant for (and a few other things as well), it's a great concept. - Dave