The powered hub is nice and opens up all kinds of possibilities. SD Cards are expensive and (relative to USB sticks) unreliable. A bad card will work fine in a camera, but make you miserable in an RPi. Without real world experience, my guess is the SD Card requirement and usage should be kept to a miniumum. Your robot doesn't need a keyboard or mouse so you have 2 free usb ports. One for a USB with J and all your cool code. The other would be a wifi USB so you talk real time with your robot.
On Tue, Jun 18, 2013 at 7:47 PM, Ian Clark <[email protected]> wrote: > Good advice! I mean to experiment with all these storage methods. > > The RPi model B has two onboard USB ports, but they're both in use for a > keyboard and a mouse. The official user guide recommends use of a powered > hub, which will make it easy to try out USBsticks and my spare USB hard > drive. > > Having installed both Dyalog APL and J801, I've nearly filled up a 4GB SD > card (the recommended entry-level). I'm about to buy a 16GB SD card, but > only because I want the elbow room to experiment with embedded systems. A > J-powered robot is a priority. I shall write up my investigations on the > wiki. > > > On Tue, Jun 18, 2013 at 3:56 PM, Eric Iverson <[email protected]>wrote: > >> You refer to the size of the RPi SD card and I wanted to point out >> that RPi is a real linux system and you can easily mount USB cards or >> even terabyte external hard drives. In general programming cases it >> probably makes sense to install J (as well as ~temp ~user etc) on a >> USB stick and reservce the SD card for the essential service of boot >> and OS. For embedded stuff (like a robot controller) it makes sense to >> put it all on the SD card. >> >> >> >> On Mon, Jun 17, 2013 at 8:40 PM, Ian Clark <[email protected]> wrote: >> > I was hoping for that, but didn't like to ask. >> > >> > debian-handbook.pdf says there are numerous front-ends to apt, and >> mentions >> > synaptic and aptitude. But I see somewhere that these are not recommended >> > for the RPi, a somewhat low-powered platform. Haven't tried them, so I >> > can't verify that. >> > >> > There are several operating systems for the RPi but the leader for now is >> > Raspbian (aka debian wheezy linux), a debian derivative (as I believe is >> > ubuntu). It's stunning what can be run on the RPi, but so far the fancier >> > UIs are more in the nature of demos, and IMO not a sound basis for >> serious >> > work. (But educational users will say: isn't everything a "demo"?) >> > >> > AFAICT the answer to "does Raspian have such-and-such"? is: if it's meant >> > to run under debian, then: yes, probably -- provided you've got a big >> > enough SD card, and don't mind a long pause. But I guess for a long time >> to >> > come the real way to put the RPi to serious work will be via the Linux >> > command line. So newbies will expect to download and install J like this: >> > >> > $ sudo apt-get install j801 >> > >> > In general I'd say, the more like the way Python does it, the better for >> > its uptake. (Until J gets its own following and can innovate confidently >> in >> > the RPi world.) >> > >> > >> > On Mon, Jun 17, 2013 at 11:11 AM, bill lam <[email protected]> wrote: >> > >> >> It is hoped that J801 can enter Raspberry Pi's official >> >> software distribution so that users can use apt to install. >> >> >> >> In ubuntu there is a gui frontend for apt but I forgot its name, >> >> are there anything similar to that in raspi? >> >> >> >> Пн, 17 июн 2013, Ian Clark писал(а): >> >> > Sure, any way of getting the J tarball onto the RPi's SD card is ok. I >> >> just >> >> > opted for direct copying because my internet connection was flaky >> (it's >> >> > fine now). >> >> > >> >> > The "conventional" way of downloading a new app is to use "apt-get" >> in a >> >> > console session, which accesses the Pi Foundation's server. This does >> >> > require your product to be sniffed-over by the Foundation. J's tarball >> >> > sidesteps all that. I see however that www.dyalog.com are delivering >> >> Dyalog >> >> > APL for the RPi by hacking into "apt", a method that might be adapted >> to >> >> J. >> >> > The only advantage I can see (apart from doing things the done way) >> is to >> >> > allow apt-get to uninstall the app as well as install it. >> >> > >> >> > >> >> > On Mon, Jun 17, 2013 at 12:26 AM, bill lam <[email protected]> >> wrote: >> >> > >> >> > > I guess you can also download directly from raspi using its >> >> > > midori (untested). >> >> > > >> >> > > Вс, 16 июн 2013, Ian Clark писал(а): >> >> > > > Björn Helgason wrote: >> >> > > > > j for rapberry is available at the i801 download >> >> > > > >> >> > > > However did I miss it? ... >> >> > > > >> >> > > > Ah, I see Bill's only just announced it. ...And it all works for >> me, >> >> > > first >> >> > > > time! >> >> > > > And very nice it looks too (Well done, Team!) >> >> > > > >> >> > > > Out of hubris, I straightaway ran the Lab: "Displaying boxed nouns >> >> > > > containing Unicode" >> >> > > > ---to my astonishment and pleasure, it worked as it should. >> >> > > > >> >> > > > ---- >> >> > > > Just for the record, here are my steps to install j801 on my RPi: >> >> > > > >> >> > > > From: http://www.jsoftware.com/download/j801/ >> >> > > > downloaded: j801a_raspi32.tar.gz -onto my iMac desktop. >> >> > > > copied it to the /boot directory of RPi's SD card (which is all >> >> you >> >> > > see >> >> > > > of it using Finder) >> >> > > > (but it seems it doesn't matter where this tarball resides) >> >> > > > >> >> > > > Then, in LXSession of RPi ... >> >> > > > >> >> > > > $ sudo tar -xzf /boot/j801a_raspi32.tar.gz >> >> > > > >> >> > > > ...creates a directory: ~/j801 (equiv to: /home/pi/j801) >> >> > > > >> >> > > > $ j801/bin/jconsole >> >> > > > >> >> > > > ...runs a j session. Once started ... >> >> > > > >> >> > > > install 'all' >> >> > > > >> >> > > > ...installs everything required (including, I guess, the binaries >> for >> >> > > jqt) >> >> > > > >> >> > > > For convenience, I created an executable file: j and copied it to >> >> /bin >> >> > > ... >> >> > > > >> >> > > > $ echo -e '#! /bin/bash\n~/j801/bin/jqt' > j >> >> > > > $ chmod +x j >> >> > > > $ sudo cp j /bin/j >> >> > > > >> >> > > > Now I can run jqt by simply entering: j >> >> > > > >> >> > > > IanClark >> >> > > > >> >> > > > >> >> > > > On Sun, Jun 16, 2013 at 8:21 AM, Björn Helgason <[email protected] >> > >> >> > > wrote: >> >> > > > >> >> > > > > j for rapberry is available at the i801 download >> >> > > > > >> >> > > > > dyalog apl is also available >> >> > > > > >> >> > > > > -- >> >> > > > > -- >> >> > > > > You received this message because you are subscribed to the >> Google >> >> > > Groups >> >> > > > > "J Programming" group. >> >> > > > > To post to this group, send email to >> >> [email protected] >> >> > > > > To unsubscribe from this group, send email to >> >> > > > > [email protected] >> >> > > > > For more options, visit this group at >> >> > > > > http://groups.google.com/group/J-Programming >> >> > > > > >> >> > > > > >> >> > > > > www.jsoftware.com >> >> > > > > --- >> >> > > > > You received this message because you are subscribed to the >> Google >> >> > > Groups >> >> > > > > "J Programming" group. >> >> > > > > To unsubscribe from this group and stop receiving emails from >> it, >> >> send >> >> > > an >> >> > > > > email to [email protected]. >> >> > > > > For more options, visit >> https://groups.google.com/groups/opt_out. >> >> > > > > >> >> > > > > >> >> > > > > >> >> > > > >> >> ---------------------------------------------------------------------- >> >> > > > For information about J forums see >> >> http://www.jsoftware.com/forums.htm >> >> > > >> >> > > -- >> >> > > regards, >> >> > > ==================================================== >> >> > > GPG key 1024D/4434BAB3 2008-08-24 >> >> > > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 >> >> > > >> ---------------------------------------------------------------------- >> >> > > For information about J forums see >> http://www.jsoftware.com/forums.htm >> >> > ---------------------------------------------------------------------- >> >> > For information about J forums see >> http://www.jsoftware.com/forums.htm >> >> >> >> -- >> >> regards, >> >> ==================================================== >> >> GPG key 1024D/4434BAB3 2008-08-24 >> >> gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 >> >> ---------------------------------------------------------------------- >> >> For information about J forums see http://www.jsoftware.com/forums.htm >> >> >> > ---------------------------------------------------------------------- >> > For information about J forums see http://www.jsoftware.com/forums.htm >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
