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Serious Problems With USB and Ethernet On the Raspberry Pi
First time accepted submitter rephlex writes "The USB controller used in the Broadcom BCM2835 (which is the SoC the Raspberry Pi uses) has buggy drivers which have been causing problems for many of its users. In addition to this, the Pi can only supply an unusually low amount of current to its USB devices, just 140 mA approximately, and using a powered hub to sidestep this limit exacerbates the issues caused by the USB drivers. Even Ethernet is affected as the Ethernet controller used on the Raspberry Pi is connected to the SoC via USB. This has resulted in packet loss and even total loss of network connectivity in certain situations. Attempts have been made in the past to fix the buggy USB drivers as there are other devices which use this problematic controller. None of these attempts seem to have achieved very much."
When you drill down relentlessly to a specific price point.
I think what people were expecting was what they were told they were going to get, not just in messages directly from the creators but in some extremely selective and breathy press coverage. Any questions about the practicality of delivering what was promised for the price were howled down on any forum on which they were posted by mobs of angry enthusiasts defending the plucky technologists inventing the new British wonder-device, so none of the practical issues were really aired until the device shipped.
By which time the 1080p HD Video was MPEG-4 only and the 35$ board that could be powered from a USB port suddenly needed its own PSU and powered hub for all practical purposes and the USB port wasn't that Universal.
And it's not just a BOM problem - true, the board originally had better power supply arrangements which were dropped to shave a couple of dollars off the board cost and to save people buying extra power adapters (how ironic) and the video codec support was limited for similar reasons - the real hardware issues seem to stem from stuff that could in principle be fixed without impacting the BOM but can't in practice owing to the closed nature of the device firmware.
What the Pi illustrates very nicely is that a working prototype is a long way from a production device and rather than learning that lesson quietly with a low-key limited production run it's being learned in the full glare of publicity and with a growing number of complaints.
Certainly the device is too cheap, but the cheaper the BOM the smaller proportion it is of the overall cost of production - and focussing on the BOM is I think where things have gone wrong. The BOM is just where the costs start.