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Cheap USB Wifi dongle supported by Linux I think :-) Surely there's one or two that are tiny and will work? Maybe this one? http://www.amazon.co.uk/7dayshop-W

Cheap USB Wifi dongle supported by Linux I think :-) Surely there's one or two that are tiny and will work? Maybe this one? http://www.amazon.co.uk/7dayshop-Wireless-150Mbps-802-11n-Adapter/dp/B004ZDRBJ6/ref=sr_1_35?ie=UTF8&qid=1322234983&sr=8-35 http://www.amazon.co.uk/7dayshop-Wireless-150Mbps-802-11n-Ad...

wolf550e 15y ago
How much power can the RaspberryPi give to the USB device? Maybe you need a separate powered USB hub.
- paulofisch 15y ago
  It depends on the (micro-USB) power supply. For the Model B (with ethernet) a 5V 1A output is recommended. At 2500mA this should be enough to supply 500mA to each of the 2xUSB ports. Many popular mobile phone chargers are micro-USB and support 5V 1A upwards.
  - wcchandler 15y ago
    This might not be the best place for this, but since you're posting on here it may seem worthwhile. I noticed you were planning on doing a couple test runs of the machining/pressing process to work out any other bugs. Are these quantities being taken out of the initial batch of components? Should there be no errors in the design, will these devices be sold off with all the other "regular" ones? If not, is there any plans to get them out to more developers? Are there any other additional dev kits to be given out prior to their release? Thanks!
    - paulofisch 15y ago
      I'm afraid I only draw pretty pictures and I'm not part of the foundation or engineering team so I know as much as has been publically posted. I imagine the 100 being made up now come from the common pool of parts. However, yields of the components and the manufacturing process could affect the initial batch size. Then again, the foundation may have accounted for this :)
rdtsc 15y ago
What about Power-over-Ethernet support?
- westbywest 15y ago
  My recollection from previous queries about this was that PoE was considered too fringe to merit the additional effort. It would complicate the PS design, since you have to convert from 48VDC or 24VDC.
  - rdtsc 15y ago
    You are probably right. Since it is a fringe feature, it would probably raise the cost quite a bit. I was thinking it would be great to have a network of these as remote sensors, or to distribute synchronized video or audio. Instead it of it being powered via the USB interface it would provide enough power via PoE to power other USB devices.
noonespecial 15y ago
Anaything with a ralink chipset seems to work fine. That's lots of realteks and generics available for less than $10 on amazon. I for one am happy the raspberry pi team isn't delaying their release to fiddle with wifi. The regulatory non-sense can literally take years per country.
- westbywest 15y ago
  I've had remarkably less than optimal experience using USB wifi dongles with rt3572 and rt2870 chipsets (IIRC) with Ubuntu kernels 2.6.28 thru 2.6.38 or so, even with the modules downloaded from Ralink directly. Inconsistent thruput, inability to change channels, and random disassociation from the AP. Plus, their modules vomit lots of pointless debug info to syslog, with no options to disable it. I'd recommend Atheros arl9170 instead.
  - noonespecial 15y ago
    I guess I should have mentioned that. Ralink is a starting point, not a finished product. Everyone manufacturer who uses them messes with the driver in their own way. The generics are the worst. Simply using the built-in drivers in ubuntu or a prebuilt module from ralink yields an almost unusable link. You have to be on your toes and willing to compile your own drivers (and even learn about the source and make tweaks) to really get ralinks to sing. The good news is that ralink makes this source freely available. Atheros's work great but they cost more (like $15 or $20 instead of $7) and you still have to be careful to get the right "mad-wifi" drivers. There are less of them though and most versions work out of the box at least acceptably. Your advice is sound though if you're just looking to get your one ras-pi on the air with minimum fuss you probably want this : http://www.amazon.com/TP-LINK-TL-WN821N-Wireless-Adapter-WPA2-PSK/dp/B002D5EIT4 http://www.amazon.com/TP-LINK-TL-WN821N-Wireless-Adapter-WPA... If you're preparing your robot army for world domination on a budget, its probably worth putting in the time to figure out a ralink. I've had great luck with this sub $7 beauty http://www.amazon.com/150mbps-Wireless-Adapter-Wifi-802-11b/dp/B003P0TEKY/ref=sr_1_5?s=electronics&ie=UTF8&qid=1322295065&sr=1-5 http://www.amazon.com/150mbps-Wireless-Adapter-Wifi-802-11b/... but it did take considerable effort to hack the driver into shape.

wolf550e 15y ago

How much power can the RaspberryPi give to the USB device? Maybe you need a separate powered USB hub.

paulofisch 15y ago
It depends on the (micro-USB) power supply. For the Model B (with ethernet) a 5V 1A output is recommended. At 2500mA this should be enough to supply 500mA to each of the 2xUSB ports. Many popular mobile phone chargers are micro-USB and support 5V 1A upwards.
- wcchandler 15y ago
  This might not be the best place for this, but since you're posting on here it may seem worthwhile. I noticed you were planning on doing a couple test runs of the machining/pressing process to work out any other bugs. Are these quantities being taken out of the initial batch of components? Should there be no errors in the design, will these devices be sold off with all the other "regular" ones? If not, is there any plans to get them out to more developers? Are there any other additional dev kits to be given out prior to their release? Thanks!
  - paulofisch 15y ago
    I'm afraid I only draw pretty pictures and I'm not part of the foundation or engineering team so I know as much as has been publically posted. I imagine the 100 being made up now come from the common pool of parts. However, yields of the components and the manufacturing process could affect the initial batch size. Then again, the foundation may have accounted for this :)

rdtsc 15y ago

What about Power-over-Ethernet support?

westbywest 15y ago
My recollection from previous queries about this was that PoE was considered too fringe to merit the additional effort. It would complicate the PS design, since you have to convert from 48VDC or 24VDC.
- rdtsc 15y ago
  You are probably right. Since it is a fringe feature, it would probably raise the cost quite a bit. I was thinking it would be great to have a network of these as remote sensors, or to distribute synchronized video or audio. Instead it of it being powered via the USB interface it would provide enough power via PoE to power other USB devices.

noonespecial 15y ago

Anaything with a ralink chipset seems to work fine. That's lots of realteks and generics available for less than $10 on amazon. I for one am happy the raspberry pi team isn't delaying their release to fiddle with wifi. The regulatory non-sense can literally take years per country.

westbywest 15y ago
I've had remarkably less than optimal experience using USB wifi dongles with rt3572 and rt2870 chipsets (IIRC) with Ubuntu kernels 2.6.28 thru 2.6.38 or so, even with the modules downloaded from Ralink directly. Inconsistent thruput, inability to change channels, and random disassociation from the AP. Plus, their modules vomit lots of pointless debug info to syslog, with no options to disable it. I'd recommend Atheros arl9170 instead.
- noonespecial 15y ago
  I guess I should have mentioned that. Ralink is a starting point, not a finished product. Everyone manufacturer who uses them messes with the driver in their own way. The generics are the worst. Simply using the built-in drivers in ubuntu or a prebuilt module from ralink yields an almost unusable link. You have to be on your toes and willing to compile your own drivers (and even learn about the source and make tweaks) to really get ralinks to sing. The good news is that ralink makes this source freely available. Atheros's work great but they cost more (like $15 or $20 instead of $7) and you still have to be careful to get the right "mad-wifi" drivers. There are less of them though and most versions work out of the box at least acceptably. Your advice is sound though if you're just looking to get your one ras-pi on the air with minimum fuss you probably want this : http://www.amazon.com/TP-LINK-TL-WN821N-Wireless-Adapter-WPA2-PSK/dp/B002D5EIT4 http://www.amazon.com/TP-LINK-TL-WN821N-Wireless-Adapter-WPA... If you're preparing your robot army for world domination on a budget, its probably worth putting in the time to figure out a ralink. I've had great luck with this sub $7 beauty http://www.amazon.com/150mbps-Wireless-Adapter-Wifi-802-11b/dp/B003P0TEKY/ref=sr_1_5?s=electronics&ie=UTF8&qid=1322295065&sr=1-5 http://www.amazon.com/150mbps-Wireless-Adapter-Wifi-802-11b/... but it did take considerable effort to hack the driver into shape.