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Bill Chennault
09-25-2011, 05:16 AM
All--

Now that the WiFi can has been kicked down the road, I am looking for other solutions. My robots tend to be relative large and with battery power to spare. I don't want a display or keyboard on the robot. So, XP/WiFi enabled single board computers appeal to me. Do you have a recommendation?

Thanks!

--Bill

Loopy Byteloose
09-25-2011, 05:24 AM
Hi Bill,
BeagleBoardXM is a popular Linux board from Digikey now. It may be able to add wifi easily and certainly will support quite a bit -- SPI, RS232, RS485, and I2C. I am not sure how to add the wifi to it, but a USB link might be the most painless.

While I love the Propeller for dedicated control of motors and sensors and such - having a file system and broader communications with the real world seems to indicate some kind of OS. And of course, we don't have much choice of OSes if we want room to play - it is a three flavored world, Apple, M$, or Unix/Linux.

Recently, I spent a lot of time reading up on SSH (secure shell) and that combined with the wifi would make your communications pretty much private.

For an XP/Wifi solution, you might as well consider a small netbook as a complete package. It is difficult to buy separate components for less that the $300USD for the package. Try EBay. One problem with an XP solution is that is it near the end of its useful life, so manufacturers of SBC have to re-evaluate the worth of carrying inventory or going to W7 or W8.

XP or any Windows is in a bit of a conflict with what you are doing as you cannot remove the GUI software from Windows, but in Linux you can leave it out in an application that doesn't require a monitor and/or keyboard. In other words, when space is at a premium, Linux has the ability to do more in less space.

Heater.
09-26-2011, 04:48 AM
Use a FEZ Cobra board from GHI together withe their FEZ WIFI Extender board. That set up has no operating system. It runs the .NET micro framework and is programmable in C#. This will be a lot easier than dealing with Linux on a Beagle or such.

Perhaps GHI has smaller cheaper WIFI set ups than the Cobra. I have not checked.

I'm wondering if its easy to use just the WIFI extender board with the Prop directly. It has SPI interface.

Or have a search for Zero-G WIFI boards.

Leon
09-26-2011, 04:55 AM
Microchip now owns Zero-G:

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=2884

I've got a couple of their PICtail Wi-Fi boards. They work very well with the PIC32 and 16-bit PICs.

Martin_H
09-26-2011, 02:12 PM
An atom based Mini-ITX board with RAM can be purchased for less than $100. But you'll also need a DC to DC power supply and some kind of mass storage. But the Windows license will set you back a significant amount, so an old netbook off e-bay might be a way to get all the parts much cheaper.

If you go the Linux route, the Chumby hacker board is ARM based, but comes with a development tool chain. It has host USB ports and can use a USB WiFi module. All together this should cost you less than $100. Plus it has some hardware interface ports built in. I've been really tempted by it.

There are others Arm/Linux boards like Gumstix as well.

Ray0665
09-26-2011, 02:20 PM
Have you checked out some of the "Plug Computer" solutions such as the Sheva or DreamPlug?
They generally run about $100 and are loaded with H/W & S/W.

RS_Jim
09-26-2011, 02:25 PM
Bill,
NetGear (and others) make wifi devices that output to an ethernet port. (around $30) that are DC powered. (5 V I think) Maybe that is a cheaper way to go. Combined with WIZ812MJ Ethernet SPI/Bus Module from Parallax would give you a cheap solution without any hardware developement.
Jim

Heater.
09-26-2011, 03:03 PM
You can still get a Zipit for $50.

http://www.amazon.com/ZIPIT-All-Wi-Fi-Messenger-Black/dp/B00115PR2O

Mine has Debian installed now. WIFI works a treat. With a couple of wires soldered on the back you have a serial link to the Prop.

Loopy Byteloose
09-26-2011, 05:28 PM
I'd just buy a used EEEpc-4g with XP installed and maybe a broken screen. You could use a monitor when you wanted via an external plug and it has wifi built in. USB to serial would be your interface. At any time, you could swap out OSes to Linux or W7.

But others are coming up with alternatives I haven't been aware of.

Martin_H
09-27-2011, 03:25 PM
FYI, here's some information on using a Chumby as a robot:

http://www.linuxtoys.org/chumbot/chumby_as_robot.pdf

Here's a video of a walker built using one:


http://www.youtube.com/watch?v=uBMvGDectjk&feature=player_embedded

The Chumby One is discontinued, but the hacker board is basically the same board as the Chumby One (minus built in WiFi). Most of the information should work with the hacker board which is still for sale. But Chumby One's show up on eBay regularly because people are upgrading to the new 8" model.

The Insignia Infocast is even cheaper and uses the Chumby design, but is made by a different manufacture. I think it is also missing the slot for the internal battery which would complicate power a bit.

Loopy Byteloose
09-28-2011, 06:44 PM
Here's a complete SBC with wifi and bluetooth for $174USD, but once again it is Linux, NOT XP

http://pandaboard.org/content/resources/getting-started

First impressions are I like this more than the BeagleBoard. Again, Digikey sells these, maybe Mouser as well.

Tor
09-29-2011, 09:45 AM
Here's a complete SBC with wifi and bluetooth for $174USD, but once again it is Linux, NOT XP

http://pandaboard.org/content/resources/getting-started

First impressions are I like this more than the BeagleBoard. Again, Digikey sells these, maybe Mouser as well.

It's a nice board. I wish it had a non-OTG USB port as well though. That's the one thing it's missing, otherwise everything is there.

-Tor

Martin_H
09-29-2011, 01:51 PM
All this chatter has pushed me to my limit. I must buy a used Insignia infocast 3.5" off eBay. They can be bought for around $34 and basically contain the Chumby hacker board. It can run off any regulated 5 volt supply, has WiFi, and enough I/O to interface with a 3.3volt microcontroller. Sounds like it and the propeller were made for each other.

mindrobots
09-29-2011, 02:44 PM
@Tor

From the latest Pandaboard documentation (pg 12 Feature Chart)

HS USB 2.0 OTG Port - Mini-AB USB connector, sourced from OMAP USB Transceiver
HS USB Host Port - Four USB HS Ports, up to 500mA current out on each, two to onboard connectors, two to expansion connectors

What type of USB support were you looking for?

Tor
09-29-2011, 03:02 PM
@Tor

From the latest Pandaboard documentation (pg 12 Feature Chart)

HS USB 2.0 OTG Port - Mini-AB USB connector, sourced from OMAP USB Transceiver
HS USB Host Port - Four USB HS Ports, up to 500mA current out on each, two to onboard connectors, two to expansion connectors

What type of USB support were you looking for?
I looked at the 'Pandaboard Connection Guide' in the link in the earlier posting. I could only find the OTG port. But now I see that there's a connector labelled '10/100 Ethernet & 2xUSB 2.0 Host ports', so then I'm all covered.

I'm not sure what they really mean by '10/100 Ethernet & 2xUSB' though - what kind of connector would that be? It looks like a single USB connector in the photo.

-Tor

mindrobots
09-29-2011, 03:19 PM
In the Reference manual .pdf I downloaded, it is a stacked connector - RJ-45 on top of 2 USB-A Connectors. From an angle shot, you can see all three connectors.

This board looks pretty darn capable. I'm going to start reading up about Linux on it and start saving money for a present for myself!

Loopy Byteloose
09-29-2011, 03:54 PM
I found I can buy one from Taiwan Digikey for about $200, though delivery is kind of unclear - not in inventory. But I have been looking at SBCs for several years and PandaBoard appears to be a real keeper.

I can use several popular distros of Linux - Ubuntu, Angstrom, and Android - plus others. I'd go with Ubuntu as I have been using it for three years now. In fact, my Toshiba netbook has Ubuntu and the total footprint is still only a bit less than 4Gbytes - software and data. I think an 8Gbyte SDcard is a lot of storage.

If you are going to get involved in Linux, understanding a bit of Unix is quite helpful as well because all the low level stuff originated in Unix. New devices - like an SPI interface are created as a file the /dev directory (in fact everything is a file in Unix/Linux). I/O is simply divided between block transfers (for mass storage) and byte stream for keyboards, sensors, etc.

And there are tons of utilities for working on custom projects with Shell scripts, Python, C, or whatever. If you want Forth, there is gForth and pForth in Ubuntu.

Bill Chennault
09-29-2011, 04:42 PM
All--

It looks like the idea of a WiFi enabled robot is very popular. I wish there were a good way to do it without resorting to a laptop or SBC.

--Bill

Loopy Byteloose
09-29-2011, 05:35 PM
Capitulation, I ordered a PandaBoard from Digikey and okay-ed a 60 day backorder as it isn't in stock. $204USD to Taiwan.

You might have better luck with ZigBee or Bluetooth, but having wireless without a seamless interface is limiting. This has both the Bluetooth and the WLAN. This looks like I could put it atop a BOEbot and it has a camera interface provided as well.

The documentation has the same street address as the BeagleBoard, so it looks as though this is a spin off of that project.

Tor
09-29-2011, 09:03 PM
In the Reference manual .pdf I downloaded, it is a stacked connector - RJ-45 on top of 2 USB-A Connectors. From an angle shot, you can see all three connectors.

This board looks pretty darn capable. I'm going to start reading up about Linux on it and start saving money for a present for myself! Thanks for the hint about the .pdf, I looked around and found it. Found the angle shot.

It's a terrific looking board. If I didn't own a Beagleboard C3 already I would get this one. Maybe if I can find a permanent project for my Beagleboard.. then I'll have an excuse to get another test/hacking board. The Panda looks like a much better upgrade than the Beagleboard Xm - the latter went to microSD, for example, and can't compete with the Pandaboard w.r.t. other interfaces. The latter seems to have just about everything possible.

-Tor

$WMc%
09-30-2011, 01:32 AM
Another Great Thread Bill...
'
WiFi...
'
The search continues.

Martin_H
10-01-2011, 01:16 AM
Well I won the Infocast auction for $20. So I should be able to hack it into a WiFi robot controller with the help of a microcontroller and an H-bridge.

Loopy Byteloose
10-01-2011, 02:42 AM
@Martin_H
A bit of envy. I hate waiting for back orders. I am even wondering if Digikey will ever deliver my PandaBoard. I see that Mouser has them in stock, but a higher cost.

Martin_H
10-06-2011, 12:41 AM
The InfoCast 3.5 (Chumby One clone) arrived. For $22 it was a bargain and definitely hackable. It's easily small enough to ride on top of a BOE bot or my CBA or TankBot for a horse/rider design. For the Propeller Platform using Forth I can then program over the WiFi via a telnet connection to the Chumby clone.

Internally it has a Tx/Rx header that I can run out through the case and interface with a microcontroller. Since it is a 3.3 volt device it will work fine with my propeller platform, but I'll need to use my level shifter for my BS2e or Arduino.

sumith
08-28-2012, 06:45 AM
Hi,

I want to establish a Wi-Fi connection between my android phone and MRF24WB0MA Wi-Fi module without router.
Is it possible? or Is there any other Wi-Fi module has the same ability to connect to a smartphone without the need of a router?

Could you please give me a solution in details.

Heater.
08-28-2012, 08:54 AM
Welcome to the forum sumith,

Unfortunately I have no suggestions for your problem. On my Galaxy S I can set it up to be a mobile access point such that my lap top connects over wifi and can use the internet via 3G. That is to say the phone becomes a wirelss router. Problem is it does not really allow the laptop (or whatever) to interact with the phone itself.

Whils we are here I would like to add to the suggestions re: Wifi via SBC.

One can now use the 25 dollar Raspberry Pi ARM board running Linux with a USB WiFi dongle. Connect that to your Prop via the Pi's UART port and there you have a cheap and simple Wifi adapter for the Prop with the added bonus of filesystem on SD card. Lot's of extra processing power. HDMI video, audio and lots of Linux goodness.

sumith
09-08-2012, 07:04 AM
Hi,

Thank you for your reply.

Mike Green
09-08-2012, 07:18 AM
I've been able to connect my Propeller boards to my iPhone using the Roving Networks' RN-174-XV which is an xBee size module designed to plug into xBee sockets. I use it with a WiFi network at home, but the firmware manual shows how you can set it up in ad-hoc mode so it can be used without a WiFi router. I haven't tried that myself. On the iPhone, I use a terminal emulator called Mocha Telnet Lite. I don't know what's available for the Android OS, but there should be equivalent programs.