From: Athanasios A. <th...@at...> - 2005-07-07 08:22:48
|
Hello All I just checked out the new breakout board which provides access to the GPIO lines and it is really really useful. Looking at all the boards again, i was thiking that as far as i can understand it, the 60pin and 92pin connectors "carry" two buses with them (Data and Adress at least, as well as the rest of the control signals). So do you consider producing boards like the tweener in the future that will be able to get pluged in in a stack, no matter the order you plug them together? (or having additional 92pin connectors to boards like the cfstix and etherstix etc) All the best. thanOS |
From: Craig H. <cr...@gu...> - 2005-07-07 19:06:27
|
On Jul 7, 2005, at 1:19 AM, Athanasios Anastasiou wrote: > I just checked out the new breakout board which provides access to > the GPIO lines and it is really really useful. It's very good-looking too. (Isn't there more to life than being really really really really really good-looking?) > Looking at all the boards again, i was thiking that as far as i can > understand it, the 60pin and 92pin connectors "carry" two buses > with them (Data and Adress at least, as well as the rest of the > control signals). The 92-pin connector does, yes -- the 60-pin connector though only carries the slow "busses" like UART lines, AC97, I2C, etc. > So do you consider producing boards like the tweener in the future > that will be able to get pluged in in a stack, no matter the order > you plug them together? (or having additional 92pin connectors to > boards like the cfstix and etherstix etc) Yes -- the tweener concept is definitely something which deserves more exploration -- the downside of a tweener design is that it pushes up the cost of board significantly, partly because the connectors are fairly expensive parts (and you'd now have 2 of them per board instead of just 1), but more importantly, for a tweener you have to pass all the signals through the board, which complicates layout significantly on these tiny little boards. For example, we're working on some dual-function 92-pin boards right now (ethernet/cf, ethernet/mmc, and dual-ethernet combos) and trying to keep those boards small while still packing in all that functionality means that we're already looking at 6 layer boards or so. Having to additionally pass all the lines through to a tightly-packed connector on the flip side of the board would really complicate routing significantly. If you have a tweener board, look at the signals coming off the connector, going to vias, and see what a spaghetti of tightly-packed lines that is. Now imagine that the tweener actually wanted to have some real functionality on it which required access to more than a tiny handful of the line from the 60-pin connector, and then imagine having 92 signals instead of just 60.... Gets pretty ugly pretty fast. Often, I think a better way to do it is to just have multi-function boards instead of stacking. That helps with physical stability too, which reduces the likelihood that a connector will separate and fry something. C |
From: Doug S. <wea...@co...> - 2005-07-08 02:49:59
|
Craig Hughes wrote: > Often, I think a better way to do it is to just have multi-function boards instead > of stacking. That helps with physical stability too, which reduces the likelihood > that a connector will separate and fry something. This is good thinking. I have been working on integrating various harware together in small spaces for a number of years, and have tried many experiments in interconnect between boards and devices. There are many standards for stacking and connecting, for example pc/104 in industrial PCs, the SIMM stick and DIMM stick backplane ideas etc. For gumstix to be "all things small" in the end result, there cannot be too many parts to snap together. Stacking even more than 2 boards makes for a fat product. For those that need multi-function, best scenario is probably a stack of only two boards, but each board wider and multi-function. Perhaps two gumstix sized boards could plug into a double width multi-function carrier, this would be approx 3.2 x 2 inches but still slim. Example carrier might be similar to the new breakout board, but with some other stuff, and a slot alongside the gumstix for another add-on like an ethernet or WiFi card. Some other discussion on the form factor/interconnect issues... I spent weeks trying to figure out which combination of gumstix parts could meet all of my needs, and I found these restrictions to be almost show-stoppers: - If you want WiFi via Cfstix, you cannot have more than a few megabytes of storage in the onboard flash. This would only be enough storage for a simple device like a router or something. I wanted to use connex but need lots of storage. I could have used cfstix/microdrive, but that adds a lot of cost/size just for storage, better to stick with MMC. I wanted WiFi but had to give up storage, so WiFi is out in favour of bluetooth. Related: - I encourage you to look at the combo WiFi/Bluetooth chips and embedded antenna that support both. This would really give gumstix an edge over other solutions. http://www.cambridgesiliconradio.com/pr/pr138.htm - The rubber duck antenna is huge, there are many embedded antennas that could be used, it would be nice if you looked into some smaller replacement. You could possibly offer different antenna options in your store, I'm willing to give up signal strength to gain ergonomics (see blackberry GSM devices, no visible antenna, but supports GSM voice, GPRS data, and bluetooth). Antennae that stick out can also break easily. Rubber duck is good for a router, bad for any kind of handheld. - If you want access to UARTs for connection to custom hardware (other microcontrollers) you cannot use AudioStix. This almost made me give up and look for larger and more expensive alternatives. I finally decided to at least try using the breakout board to an external audio codec. At the moment I am wishing that the breakout boards had either a footer for UCB1400 or even better one installed, but I realize that you can't please everyone :) The AC97 signals on breakout can easily connect to audio codec on a proto adapter for testing, then a custom PCB when it all works. However, you were very close to me not needing much custom hardware at all, and simple external connections rather than high density (very desireable). So I think that the move towards multi-function boards is a good idea. The right combination of gumstix and multi-function carrier will always be smaller and more robust than several boards connected together. - I have struggled a lot with storage issues. The current use of MMC is very good, small and cheap, but there is huge demand for storage these days. It's encouraging that you're adding storage to some peripherals like ethernet, would be a good idea to add them to others, and to breakout boards. Another thing I have been eyeing very closely is toshiba 1.8" drives like in iPOD, which are becoming cheap commodity items with tons of storage (now up to 60GB I think). Sure would be nice to interface those. What I like about Gumstix is the low entry cost (no expensive devkit purchase reqd) and the store format, pick and choose what you need. I have looked at ALL of the available PXA2xx boards and most are very expensive to even try, and difficult to interface. I have noticed that most of the carrier boards are very large too, usually in the neighborhood of 4x4 or 4x6 inches (and expensive!). This is the size of industrial/embedded PC and at least part of the point of going x-scale is going small (and low power). So back to the multi-function idea: I bet if you ask the average person what features they need, those could best be laid out in a stack of 2 board height, approx 3.2 x 2 inches. A nicely designed bottom board would be very flexible if there was exposed 92 and 60 pin sockets. Plug in the gumstix of choice, one add-in of choice (or gumstix sized custom board), and the other signals you need are available on the bottom board. Just food for thought. -- Doug |
From: Jeremy G. <je...@ru...> - 2005-07-08 05:06:33
|
I just ordered a cfstix pack and have been contemplating the WiFi space problem for a while. I've come to the conclusion that I'll use the little space the gumstix gives me to write a few scripts to get a WiFi connection up and mount an NFS share on a nice 80 GB drive. File I/O performance won't be nearly as good, but it should work fairly well. This will also give me the ability to run multiple gumstix of the same NFS share and have them share data transparently through the filesystem. The other option I've been considering would be a CF usb host card to drive a WiFi dongle and an external hard drive. I have two major concerns with this type of setup: Power usage and Size. I would probably tack on another set of batteries or something and splice them into the usb cables to provide that 5v to save the gumstix batteries. As far as size, I'll have to look into these external laptop drives but as I recall, they can be somewhat expensive. -- Jeremy Grosser www.runemonkey.com On Jul 7, 2005, at 10:48 PM, Doug Sutherland wrote: > Craig Hughes wrote: > > > Often, I think a better way to do it is to just have multi-function > boards instead > > of stacking. That helps with physical stability too, which reduces > the likelihood > > that a connector will separate and fry something. > > This is good thinking. I have been working on integrating various > harware together in > small spaces for a number of years, and have tried many experiments in > interconnect > between boards and devices. There are many standards for stacking and > connecting, for > example pc/104 in industrial PCs, the SIMM stick and DIMM stick > backplane ideas etc. > For gumstix to be "all things small" in the end result, there cannot > be too many parts > to snap together. Stacking even more than 2 boards makes for a fat > product. For those > that need multi-function, best scenario is probably a stack of only > two boards, but > each board wider and multi-function. > > Perhaps two gumstix sized boards could plug into a double width > multi-function carrier, > this would be approx 3.2 x 2 inches but still slim. Example carrier > might be similar > to the new breakout board, but with some other stuff, and a slot > alongside the gumstix > for another add-on like an ethernet or WiFi card. Some other > discussion on the form > factor/interconnect issues... > > I spent weeks trying to figure out which combination of gumstix parts > could meet all > of my needs, and I found these restrictions to be almost show-stoppers: > > - If you want WiFi via Cfstix, you cannot have more than a few > megabytes of storage > in the onboard flash. This would only be enough storage for a simple > device like > a router or something. I wanted to use connex but need lots of > storage. I could > have used cfstix/microdrive, but that adds a lot of cost/size just > for storage, > better to stick with MMC. I wanted WiFi but had to give up storage, > so WiFi is > out in favour of bluetooth. Related: > > - I encourage you to look at the combo WiFi/Bluetooth chips and > embedded antenna > that support both. This would really give gumstix an edge over > other solutions. > http://www.cambridgesiliconradio.com/pr/pr138.htm > > - The rubber duck antenna is huge, there are many embedded antennas > that could be > used, it would be nice if you looked into some smaller > replacement. You could > possibly offer different antenna options in your store, I'm > willing to give up > signal strength to gain ergonomics (see blackberry GSM devices, > no visible > antenna, but supports GSM voice, GPRS data, and bluetooth). > Antennae that > stick out can also break easily. Rubber duck is good for a > router, bad for any > kind of handheld. > > - If you want access to UARTs for connection to custom hardware (other > microcontrollers) > you cannot use AudioStix. This almost made me give up and look for > larger and more > expensive alternatives. I finally decided to at least try using the > breakout board > to an external audio codec. At the moment I am wishing that the > breakout boards had > either a footer for UCB1400 or even better one installed, but I > realize that you > can't please everyone :) The AC97 signals on breakout can easily > connect to audio > codec on a proto adapter for testing, then a custom PCB when it all > works. However, > you were very close to me not needing much custom hardware at all, > and simple > external connections rather than high density (very desireable). So I > think that > the move towards multi-function boards is a good idea. The right > combination of > gumstix and multi-function carrier will always be smaller and more > robust than > several boards connected together. > > - I have struggled a lot with storage issues. The current use of MMC > is very good, > small and cheap, but there is huge demand for storage these days. > It's encouraging > that you're adding storage to some peripherals like ethernet, would > be a good idea > to add them to others, and to breakout boards. Another thing I have > been eyeing > very closely is toshiba 1.8" drives like in iPOD, which are becoming > cheap > commodity items with tons of storage (now up to 60GB I think). Sure > would be nice > to interface those. > > What I like about Gumstix is the low entry cost (no expensive devkit > purchase reqd) > and the store format, pick and choose what you need. I have looked at > ALL of the > available PXA2xx boards and most are very expensive to even try, and > difficult to > interface. I have noticed that most of the carrier boards are very > large too, > usually in the neighborhood of 4x4 or 4x6 inches (and expensive!). > This is the size > of industrial/embedded PC and at least part of the point of going > x-scale is going > small (and low power). So back to the multi-function idea: I bet if > you ask the > average person what features they need, those could best be laid out > in a stack > of 2 board height, approx 3.2 x 2 inches. A nicely designed bottom > board would > be very flexible if there was exposed 92 and 60 pin sockets. Plug in > the gumstix > of choice, one add-in of choice (or gumstix sized custom board), and > the other > signals you need are available on the bottom board. Just food for > thought. > > -- Doug > > > ------------------------------------------------------- > This SF.Net email is sponsored by the 'Do More With Dual!' webinar > happening > July 14 at 8am PDT/11am EDT. We invite you to explore the latest in > dual > core and dual graphics technology at this free one hour event hosted > by HP, AMD, and NVIDIA. To register visit > http://www.hp.com/go/dualwebinar > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Dave S. <da...@sm...> - 2005-07-08 13:29:27
|
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 8 Jul 2005, at 06:06, Jeremy Grosser wrote: > As far as size, I'll have to look into these external laptop =20 > drives but as I recall, they can be somewhat expensive. If you have access to a 2.5" HD, you can by the external casing for =20 not a lot of money. I got a USB2/FW400 one for about =A325 from =20 www.directusbstore.co.uk (might be .com). I bought a 80Gb drive for =20 this laptop for about =A380 and put the original 40Gb in the external =20= caddy. Regards, Dave -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (Darwin) iD8DBQFCziMH5JkwKL6aQOQRAhKSAJ0ebJvpMQ24JoLyGnYJ7wlu38EjjgCgytI5 YIBzm4U1xM2WfukhFkvfDfw=3D =3D+Ubi -----END PGP SIGNATURE----- |
From: Craig H. <cr...@gu...> - 2005-07-08 19:10:01
|
On Jul 7, 2005, at 10:06 PM, Jeremy Grosser wrote: > I just ordered a cfstix pack and have been contemplating the WiFi > space problem for a while. I've come to the conclusion that I'll > use the little space the gumstix gives me to write a few scripts to > get a WiFi connection up and mount an NFS share on a nice 80 GB > drive. File I/O performance won't be nearly as good, but it should > work fairly well. This will also give me the ability to run > multiple gumstix of the same NFS share and have them share data > transparently through the filesystem. You might actually find that file I/O is substantially *better* using an NFS mounted drive than using the local flash. Flash on the gumstix is pretty slow, slowed further by the compression layer that JFFS2 puts on top of it. By contrast, reading/writing NFS at 11MBps where the underlying hardware is a high-RPM drive would likely be a lot faster, at least in bandwidth terms. Latency might be slightly longer, but probably not by much, due to the JFFS2 compression/ uncompression. > The other option I've been considering would be a CF usb host card > to drive a WiFi dongle and an external hard drive. I have two major > concerns with this type of setup: Power usage and Size. I would > probably tack on another set of batteries or something and splice > them into the usb cables to provide that 5v to save the gumstix > batteries. As far as size, I'll have to look into these external > laptop drives but as I recall, they can be somewhat expensive. yuck, what an ugly pile of wires that'd be :) C |
From: Jeremy G. <je...@ru...> - 2005-07-09 02:40:33
|
On Jul 8, 2005, at 3:09 PM, Craig Hughes wrote: <snip>NFS over WiFi > You might actually find that file I/O is substantially *better* using > an NFS mounted drive than using the local flash. Flash on the gumstix > is pretty slow, slowed further by the compression layer that JFFS2 > puts on top of it. By contrast, reading/writing NFS at 11MBps where > the underlying hardware is a high-RPM drive would likely be a lot > faster, at least in bandwidth terms. Latency might be slightly > longer, but probably not by much, due to the JFFS2 > compression/uncompression. <snip>CF USB > > yuck, what an ugly pile of wires that'd be :) > > C > Thanks for the input on NFS performance compared to Flash, however I've also started wondering if a USB thumb drive would be well suited to this type of service. The USB2 models are getting really cheap and AFAIK most of them draw about 100 mW off the USB port... Not great, but certainly better than a mechanical drive. As far as a mess of wires, I'm not too worried... It can't be much worse than the system I'm replacing. For the curious, I'm using a cheap RC car chassis as a base for a robot that will be mapping a building. I've already got it computer controlled by wiring the transmitter it came with to a parallel port. The problem I ran into is that this only allows for one-way communication with the car and isn't particularly accurate about motor control. So, I'm replacing the RC car's receiver board with a gumstix and I'm planning to wire up the motors to a custom board with some relays connected to the gumstix GPIOs... I might be buying a robostix in the near future so that I can do PWM without much more work. Once I can reproduce my control program on the gumstix (I wrote a little logo-ish interpreter for the parallel port implementation) I will start work on sensor inputs. I am currently researching location detection using methods other than GPS as GPS requires line of sight to at least three satellites and this robot is designed to work indoors, without line of sight to anything. I'm looking at projects like http://www.herecast.com/ to do location using WiFi signals but I will probably end up using a custom beacon/ping system with known coordinates of the stations so that I can do triangulation. I'm open to suggestions from other gumstix users. -- Jeremy Grosser www.runemonkey.com |
From: Aleksandar M. <ama...@gm...> - 2005-07-09 03:33:09
|
At one point in my career, I was on a research project, working for a large= =20 IT organization whose name has 3 letters, and it's color is blue in NY... Well, the research involved = a=20 navigating system for blind people in buildings (they would carry a small computer with them) -- it was a fun=20 research project... The way it=20 would work is as follows: You place RFIDs on walls of the building, and important places. We would=20 first take floor-plans of the building (AutoCAD files), I wrote some code in VB and AutoLISP that would= =20 let a user "place" using a mouse the RFIDs on the plan. My code would then go through the drawing,= =20 and generate a small XML file, that would have all RFIDs with their exact location (distance=20 between each other etc). A custodian or building techs, would go around with the map with RFIDs, and= =20 place them on the wall and other places, as indicated by the AutoCAD drawing I generated. Then,=20 this small computer would have an RFID reader, and as they enter the building, the WIFI enabled= =20 hand held computer would initiate the RFID XML file download. With our research project ( we would= =20 have a laptop on a carry platform ), we would enter the location where we want to go (obviously a=20 blind person would rely on voice recgnition) - let's say "Mr. Jones" -- the computer would figure= =20 out how to get there, and as this person is walking through the hallways, it would read the RFID tags,= =20 and it would tell the person, turn left, turn right etc... Some of the realy weird problems I encountered were things like -- making= =20 sure a person does not bump into a wall, elevators, escalators, fire exits etc... Also, elevators= =20 out of commission were a separate problem... All in all, it was a fun project, and I learned a lot doing it... Cheers, Alex. On 7/8/05, Jeremy Grosser <je...@ru...> wrote: >=20 > On Jul 8, 2005, at 3:09 PM, Craig Hughes wrote: > <snip>NFS over WiFi > > You might actually find that file I/O is substantially *better* using > > an NFS mounted drive than using the local flash. Flash on the gumstix > > is pretty slow, slowed further by the compression layer that JFFS2 > > puts on top of it. By contrast, reading/writing NFS at 11MBps where > > the underlying hardware is a high-RPM drive would likely be a lot > > faster, at least in bandwidth terms. Latency might be slightly > > longer, but probably not by much, due to the JFFS2 > > compression/uncompression. > <snip>CF USB > > > > yuck, what an ugly pile of wires that'd be :) > > > > C > > > Thanks for the input on NFS performance compared to Flash, however I've > also started wondering if a USB thumb drive would be well suited to > this type of service. The USB2 models are getting really cheap and > AFAIK most of them draw about 100 mW off the USB port... Not great, but > certainly better than a mechanical drive. >=20 > As far as a mess of wires, I'm not too worried... It can't be much > worse than the system I'm replacing. >=20 > For the curious, I'm using a cheap RC car chassis as a base for a robot > that will be mapping a building. I've already got it computer > controlled by wiring the transmitter it came with to a parallel port. > The problem I ran into is that this only allows for one-way > communication with the car and isn't particularly accurate about motor > control. >=20 > So, I'm replacing the RC car's receiver board with a gumstix and I'm > planning to wire up the motors to a custom board with some relays > connected to the gumstix GPIOs... I might be buying a robostix in the > near future so that I can do PWM without much more work. Once I can > reproduce my control program on the gumstix (I wrote a little logo-ish > interpreter for the parallel port implementation) I will start work on > sensor inputs. >=20 > I am currently researching location detection using methods other than > GPS as GPS requires line of sight to at least three satellites and this > robot is designed to work indoors, without line of sight to anything. > I'm looking at projects like http://www.herecast.com/ to do location > using WiFi signals but I will probably end up using a custom > beacon/ping system with known coordinates of the stations so that I can > do triangulation. >=20 > I'm open to suggestions from other gumstix users. > -- > Jeremy Grosser > www.runemonkey.com <http://www.runemonkey.com> >=20 >=20 >=20 > ------------------------------------------------------- > This SF.Net <http://SF.Net> email is sponsored by the 'Do More With Dual!= '=20 > webinar happening > July 14 at 8am PDT/11am EDT. We invite you to explore the latest in dual > core and dual graphics technology at this free one hour event hosted by= =20 > HP, > AMD, and NVIDIA. To register visit http://www.hp.com/go/dualwebinar > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Jeremy G. <je...@ru...> - 2005-07-09 06:22:46
|
I've actually been looking into RFID for another project I have in mind=20= for home automation. I would place RFID tags above all of the doors in=20= the house and have a small necklace sized device that would act as a=20 repeater of the RFID signal. It would repeat it on a separate channel=20 to be received at a hardwired control system that could dim lights,=20 send wake-on-lan packets, etc. If only I had the money and the time to=20= make such a thing possible... -- Jeremy Grosser www.runemonkey.com On Jul 8, 2005, at 11:32 PM, Aleksandar Matijaca wrote: > > At one point in my career, I was on a research project, working for a=20= > large IT organization whose name > has 3 letters, and it's color is blue in NY...=A0 Well, the research=20= > involved a navigating system for blind people in > buildings (they would carry a small computer with them) -- it was a=20= > fun research project...=A0 The way it > would work is as follows: > > You place RFIDs on walls of the building, and important places.=A0 We=20= > would first take floor-plans of the > building (AutoCAD files), I wrote some code in VB and AutoLISP that=20= > would let a user "place" using > a mouse the RFIDs on the plan.=A0 My code would then go through the=20= > drawing, and generate a small > XML file, that would have all RFIDs with their exact location=20 > (distance between each other etc). > > A custodian or building techs, would go around with the map with=20 > RFIDs, and place them on the wall > and other places, as indicated by the AutoCAD drawing I generated.=A0=20= > Then, this small computer > would have an RFID reader, and as they enter the building, the WIFI=20= > enabled hand held computer would > initiate the RFID XML file download.=A0 With our research project ( = we=20 > would have a laptop on a carry > platform ), we would enter the location where we want to go=20 > (obviously a blind person would rely > on voice recgnition) - let's say "Mr. Jones" -- the computer would=20 > figure out how to get there, and as > this person is walking through the hallways, it would read the RFID=20= > tags, and it would tell the > person, turn left, turn right etc... > > Some of the realy weird problems I encountered were things like --=20 > making sure a person does not > bump into a wall, elevators, escalators, fire exits etc...=A0 Also,=20= > elevators out of commission were > a separate problem... > > All in all, it was a fun project, and I learned a lot doing it... > > Cheers, Alex. |
From: Aleksandar M. <ama...@gm...> - 2005-07-09 14:07:06
|
I like the idea of a repeater. Unfortunately, all house automation projects= =20 that I have seen seem to be 'turn/on turn/off' kind of things. It would seem to me, that all= =20 of these projects universaly seem to be 'low level' kind of automation. It would be much more= =20 interesting to develop things that can truly interact, use some kind of AI etc... As yo= u=20 said, all it takes is money and time... Cheers, a.m. On 7/9/05, Jeremy Grosser <je...@ru...> wrote: >=20 > I've actually been looking into RFID for another project I have in mind > for home automation. I would place RFID tags above all of the doors in > the house and have a small necklace sized device that would act as a > repeater of the RFID signal. It would repeat it on a separate channel > to be received at a hardwired control system that could dim lights, > send wake-on-lan packets, etc. If only I had the money and the time to > make such a thing possible... > -- > Jeremy Grosser > www.runemonkey.com <http://www.runemonkey.com> >=20 >=20 > On Jul 8, 2005, at 11:32 PM, Aleksandar Matijaca wrote: > > > > At one point in my career, I was on a research project, working for a > > large IT organization whose name > > has 3 letters, and it's color is blue in NY... Well, the research > > involved a navigating system for blind people in > > buildings (they would carry a small computer with them) -- it was a > > fun research project... The way it > > would work is as follows: > > > > You place RFIDs on walls of the building, and important places. We > > would first take floor-plans of the > > building (AutoCAD files), I wrote some code in VB and AutoLISP that > > would let a user "place" using > > a mouse the RFIDs on the plan. My code would then go through the > > drawing, and generate a small > > XML file, that would have all RFIDs with their exact location > > (distance between each other etc). > > > > A custodian or building techs, would go around with the map with > > RFIDs, and place them on the wall > > and other places, as indicated by the AutoCAD drawing I generated. > > Then, this small computer > > would have an RFID reader, and as they enter the building, the WIFI > > enabled hand held computer would > > initiate the RFID XML file download. With our research project ( we > > would have a laptop on a carry > > platform ), we would enter the location where we want to go > > (obviously a blind person would rely > > on voice recgnition) - let's say "Mr. Jones" -- the computer would > > figure out how to get there, and as > > this person is walking through the hallways, it would read the RFID > > tags, and it would tell the > > person, turn left, turn right etc... > > > > Some of the realy weird problems I encountered were things like -- > > making sure a person does not > > bump into a wall, elevators, escalators, fire exits etc... Also, > > elevators out of commission were > > a separate problem... > > > > All in all, it was a fun project, and I learned a lot doing it... > > > > Cheers, Alex. >=20 >=20 >=20 > ------------------------------------------------------- > This SF.Net <http://SF.Net> email is sponsored by the 'Do More With Dual!= '=20 > webinar happening > July 14 at 8am PDT/11am EDT. We invite you to explore the latest in dual > core and dual graphics technology at this free one hour event hosted by= =20 > HP, > AMD, and NVIDIA. To register visit http://www.hp.com/go/dualwebinar > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |