An FYI for folks wanting to get into RaspPi, they're coming out with a new revision that seems to be improved as far as power management and mounting goes:
Looks like adafruit is giving away Pis with orders over 350 - I assume to make room for the new ones? http://adafruit.com/products/998
As far as I know, Adafruit is not an authorized Pi distributor (that is still exclusive to Allied & RS, and their subsidiaries) and they do not sell the Pi board separately. So they must have bought some through the normal retail channel- I doubt they have a large stock.
That makes sense. I tried to see what they were selling it for, but obviously couldn't find a pricetag. Like you said, it must be just an internal stock they acquired. Either way, sounds like new ones are in production!
My current project is pretty mundane. I have three OCXO (ovenized oscillators) and one GPS unit. Each produces a 1-PPS (pulse per second) signal. I am studying the stability and drift over time of the oscillators. The Prop takes these four inputs (one per cog) and records a time-stamp on the rising edge based on its system clock, 100 MHz in my case, for 10 ns timing resolution. Then the elapsed seconds, 1 PPS duration of channel 1 (as a delta from 1E8 clock ticks), and the pairwise timestamp deltas between channels T2-1, T3-1, T4-1, T3-2, T4-2, T4-3 are sent via a serial-to-USB link to the R-Pi. The R-Pi logs the data to CF card, and also every half-hour, uploads the previous hour's worth of data, plus a 10-second brief excerpt to my website, for downloading and plotting elsewhere (for example, see attached plot. Top six graphs are the linear trends, bottom two show the residuals. Bottom right is the Ch.1-2-3 residuals vs. Ch.4 GPS, which has a 60 ns "sawtooth" characteristic, giving the wider trace).
In this application the Prop does the real-time measurement by capturing the edge timings, and the R-Pi is just doing mass storage and network uplink. For this job the R-Pi could (for example) be replaced by an Arduino with CF card + ethernet shield, but I believe that combo would actually be more expensive than a Pi. Also, coding on the Pi side was quite fast and easy with the power of shell scripting and all the usual Unix-ish command-line utilities. Here, the Pi is using maybe 1% of its resources so it could be doing many other things as well. It could be generating the graphs also, for example (I use the KST plotting tool- NumPy / SciPy is even more powerful). Before the Pi I would have used my desktop PC, but that uses about 100 W, and the Pi draws only about 2 W so I don't worry about leaving it on all the time.
It might be interesting to have the prop receive the 1PPS from the GPS, and have an output driving a heater connected to its crystal. From there, it could basically adjust its own clock in a PLL-like fashion to have a stable clock, which could then be used as a timebase to compare your OCXOs against.
As far as I know, Adafruit is not an authorized Pi distributor (that is still exclusive to Allied & RS, and their subsidiaries) and they do not sell the Pi board separately. So they must have bought some through the normal retail channel- I doubt they have a large stock.
Yes I wondered that too. Apart from RS/Allied, the other dist group is Element14/Farnell/Newark/MCMelectronics
@JBeale: Thanks for sharing the details. Time is a fascinating thing to measure. Somewhere in the pile I've got an SC-cut, 5th overtone OCXO that I dote over. It's big, and the heater consumes a fair amount of power (in terms of modern sensibilities at least). But it requires infinitely less maintenance than a rubidium source or a hydrogen maser.
So are you using an SD card, a TV, and the official R-Pi keyboard, or have you gone fancier than that? Have you done any programming on the R-Pi other than in scripting language?
I really like the idea of maximizing the use of the R-Pi without investing heavily in add-ons. (Laptops I have.) Your example seems to illustrate a useful capability that requires very little added expense. Thanks!
Actually, I find it easiest to work with the Pi through a serial terminal into its onboard UART, from my regular desktop PC. I've also tried running it as a standalone with keyboard and mouse and DVI monitor, which works, but as I am working I frequently refer to web pages for various info, and the Pi's own GUI and web browser are not responsive enough for my taste. Which is fine, I don't really need it to be a web browser. As an embedded system with ethernet, USB and relatively spacious memory it is quite useful for my simple data-acquisition needs. (If they ever get hardware-accelerated X Windows going, it would help, but in any case a 700 MHz ARMv6 is not going to compare with a modern desktop machine.)
I only threw those YouTube and Google hit counts in there because you opened by saying you had not found much Raspi action. They show there is quite a bit. But yes, hit counts don't mean much.
I'm very surprised that you only found two individuals logged into the Rasp forums. One of them would have been me:) I have been logged into there continuously for a month or so. Normally when I take a look there are hundreds of people on line.
Where does one keep tabs on this sort of thing? Is it on raspberrypi.org?
Yes, the net fills up with junk very quickly, be it just repetition, whining, obsolete or wrong info. Who on earth is going to watch those thousands of Raspi videos?
Rant: Why does everyone now feel the need to say everything via a video now a days? Did they forget how to write? With a text you can quickly skip through and see it might me what you are looking for or do a search on it. With a vid you have to sit through the whole thing before you find out it is useless chatter.
I have only been checking the raspberrypi.org front page and lurking on the forum for a bit. They have so many sub forums it's hard to keep up with. What with the plethora of languages operating systems etc etc.
which is a Linux board using a 1 GHz Allwinner A10 (Cortex A8). 1GB of DDR3 RAM, 96 IO pins, SATA, HDMI, 2x USB host, 1xUSB OTG, for $49.
It will be interesting to see what the state of the software is on this board. There is allegedly no documentation at all for the Allwinner chips, they just rely on a reference design.
I gotta admit I'm a sucker for cheap ARM boards. Evidently I'm not alone. The CubieBoard in particular is calling my name right now... I love the onboard esata+ connector. Makes life a lot easier.
@JBeale: Perfect. I'm taking the Pi plunge today. Bag the keyboard and all the other trappings.
@Heater: I share your frustration over the proliferation of videos. I first became irritated with that on news websites, where I wanted a bit of text to scan but was forced to load and watch a video to learn more. Forget it.
Also, it seems pretty clear I didn't give raspberrypi.org a fair shake. Once again, I was scanning for quick answers, and the sample posts I selected to read were not inspiring or engaging, or really going anywhere.
User Name,
Ha, Just search for "Heater" on the Raspi forums to find out where the action is:)
There must be some other Parallaxians there as well by now.
That is great news and something of an amazing achievment in this modern world of Asian everything. But it really put my mind in a Spin. I mean it's a plant bellonging to the evil Sony corporation. Any way can't wait to get my "Made in UK" Pi.
VHDL is more like the PLD tools I began with. Unfortunately Verilog is all I have right now. What tools come on the DE0-Nano CDs? Anything useful in that regard?
This is exactly the sort of website I expected to find on the R-Pi. It is clear, concise, complete, and to-the-point. I'm surprised how many months passed before it appeared. Perhaps it is a reflection of the fact that supply has finally caught up with demand. Why field articles for devices your readers can't get hold of?
Nicely done intro to the Pi. But all that info is on the rasperrypi.org site. Don't forget it's early days, this was only intended a prelaunch for developers and it mushroomed beyond anyones expectations.
Why field articles for devices your readers can't get hold of?
I don't know, there are 15000 Raspies on the map here, http://rastrack.co.uk/ which is estimated to be a lot less than ten percent of what's been shipped. Looks like a million Raspies will have been shipped by Christmas, not bad going.
I noticed on the RPi site, a discussion about overclocking the RPi, has anybody tried this? If you have, does it make any noticeable difference in how the GUI reacts at that speed? Faster, much faster, desirable faster?
I guess I answered my own question. I had to re-image my SD card for a new install, so I downloaded the latest wheezy raspian.
In the raspi-config there is a new selection for overclocking, so to do over-clocking, it has become a painless procedure. I am now
running the RPi at 1GHz, still have not decided as to whether it makes a bit of difference. Hope somebody else tries it, to see
how it works for them.
I am waiting on delivery of a MK802 II that I snatched on eBay for A$51. It's much faster than the RPi so interested to see how it performs - like the wifi instead of ethernet.
Comments
http://www.raspberrypi.org/archives/1929
Looks like adafruit is giving away Pis with orders over 350 - I assume to make room for the new ones?
http://adafruit.com/products/998
As far as I know, Adafruit is not an authorized Pi distributor (that is still exclusive to Allied & RS, and their subsidiaries) and they do not sell the Pi board separately. So they must have bought some through the normal retail channel- I doubt they have a large stock.
In this application the Prop does the real-time measurement by capturing the edge timings, and the R-Pi is just doing mass storage and network uplink. For this job the R-Pi could (for example) be replaced by an Arduino with CF card + ethernet shield, but I believe that combo would actually be more expensive than a Pi. Also, coding on the Pi side was quite fast and easy with the power of shell scripting and all the usual Unix-ish command-line utilities. Here, the Pi is using maybe 1% of its resources so it could be doing many other things as well. It could be generating the graphs also, for example (I use the KST plotting tool- NumPy / SciPy is even more powerful). Before the Pi I would have used my desktop PC, but that uses about 100 W, and the Pi draws only about 2 W so I don't worry about leaving it on all the time.
Yes I wondered that too. Apart from RS/Allied, the other dist group is Element14/Farnell/Newark/MCMelectronics
So are you using an SD card, a TV, and the official R-Pi keyboard, or have you gone fancier than that? Have you done any programming on the R-Pi other than in scripting language?
I really like the idea of maximizing the use of the R-Pi without investing heavily in add-ons. (Laptops I have.) Your example seems to illustrate a useful capability that requires very little added expense. Thanks!
I only threw those YouTube and Google hit counts in there because you opened by saying you had not found much Raspi action. They show there is quite a bit. But yes, hit counts don't mean much.
I'm very surprised that you only found two individuals logged into the Rasp forums. One of them would have been me:) I have been logged into there continuously for a month or so. Normally when I take a look there are hundreds of people on line. Yes, the net fills up with junk very quickly, be it just repetition, whining, obsolete or wrong info. Who on earth is going to watch those thousands of Raspi videos?
Rant: Why does everyone now feel the need to say everything via a video now a days? Did they forget how to write? With a text you can quickly skip through and see it might me what you are looking for or do a search on it. With a vid you have to sit through the whole thing before you find out it is useless chatter.
I have only been checking the raspberrypi.org front page and lurking on the forum for a bit. They have so many sub forums it's hard to keep up with. What with the plethora of languages operating systems etc etc.
which is a Linux board using a 1 GHz Allwinner A10 (Cortex A8). 1GB of DDR3 RAM, 96 IO pins, SATA, HDMI, 2x USB host, 1xUSB OTG, for $49.
It will be interesting to see what the state of the software is on this board. There is allegedly no documentation at all for the Allwinner chips, they just rely on a reference design.
https://www.olimex.com/dev/a13-olinuxino.html
@JBeale: Perfect. I'm taking the Pi plunge today. Bag the keyboard and all the other trappings.
@Heater: I share your frustration over the proliferation of videos. I first became irritated with that on news websites, where I wanted a bit of text to scan but was forced to load and watch a video to learn more. Forget it.
Also, it seems pretty clear I didn't give raspberrypi.org a fair shake. Once again, I was scanning for quick answers, and the sample posts I selected to read were not inspiring or engaging, or really going anywhere.
Ha, Just search for "Heater" on the Raspi forums to find out where the action is:)
There must be some other Parallaxians there as well by now.
Yep, you don't need much if you just want to work through a shell prompt. Here's a convenient way to work with the Pi through a USB-serial link. Just 4 wires, and no separate power supply needed!
https://picasaweb.google.com/lh/photo/tGgcfLKxu-WwtoR-yA9tXtMTjNZETYmyPJy0liipFm0?feat=directlink
For my USB-to-3V3-Serial adaptor I used this, under $2 shipped (how do they do that?) Although a USB extension cable is also handy.
http://www.ebay.com/itm/USB-To-RS232-TTL-PL2303HX-Auto-Converter-Module-Converter-Adapter-5V-3-3V-Output-/350568364250
You can also just work remotely via telnet or SSH into the Pi, over the network, but you'll still need a power supply connection plus the network.
http://www.bbc.co.uk/news/technology-19510040
That is great news and something of an amazing achievment in this modern world of Asian everything. But it really put my mind in a Spin. I mean it's a plant bellonging to the evil Sony corporation. Any way can't wait to get my "Made in UK" Pi.
Could have helped last week. I am going to recreate my sd card again to use the correct answers.
I don't know, there are 15000 Raspies on the map here, http://rastrack.co.uk/ which is estimated to be a lot less than ten percent of what's been shipped. Looks like a million Raspies will have been shipped by Christmas, not bad going.
Ray
In the raspi-config there is a new selection for overclocking, so to do over-clocking, it has become a painless procedure. I am now
running the RPi at 1GHz, still have not decided as to whether it makes a bit of difference. Hope somebody else tries it, to see
how it works for them.
Ray
I truly don't know how they do that. But they do. My adapters just arrived - and they work great. I found the PL2303 driver here.