Hello Alex,>> >>>The advantage is that it doesn't need a hole, just a translucent section >>>in the enclosure. >> >>I agree, this is a significant advantage. Probably the way to go if you >>have >>to be waterproof - you will still be able to make 10 bpS easily, which >>at your >>1 - 2 K is still adequate (vs. the 300 bpS of Kansas City). >>The main disadvantage I see is the necessity to write some modulation >>software for Windows (yuck). > > > Could always use an ipod screen. > Make a "music video" that has the correct modulation. >I guess the fact that I don't have an iPod (and never had the desire to own one...) shows my age ;-) -- Regards, Joerg http://www.analogconsultants.com
WLAN card to generate pulsed RF?
Started by ●October 26, 2006
Reply by ●October 29, 20062006-10-29
Reply by ●October 29, 20062006-10-29
Hello Jasen,>> >>>>The only other option I could think of (and I have done that before) is >>>>to provide a photodiode and let the LCD screen flash. However, that is >>>>really slow and can annoy others who have to work close to that laptop. >>> >>> >>>Why not use the audio output of the laptop? Every laptop has one and >>>it is very easy to program. If you get really nifty, you can >>>distribute your firmware as an mp3 file. >>> >>>Still, I think USB really is the sensible way to go for these sort of >>>things. USB to serial adapter chips are commonly available and small >>>(like the CP2101). Cabling is not an issue if you use standard >>>(miniature) USB sockets. Drivers can be made available from your >>>website. >>> >> >>Either one needs cables. People forget to take them along, they can be >>damaged, connectors become dirty, it could be raining or snowing etc. >>The audio port on laptops is a 3.5mm audio jack. Those are IMHO rather >>unreliable. USB is bulky and expensive. > > > audio needs a microphone built into the device and a demodulator, > no cabling. >Yes, that's the other option we had discussed here in the thread. However, that would usually require a hole in the device for the microphone. Not really a good option for outdoor stuff. Maybe thinning the enclosure over the mike would be enough though. -- Regards, Joerg http://www.analogconsultants.com
Reply by ●October 29, 20062006-10-29
Hello Jasen,>> >>Not really since the field strength two feet from a laptop will be >>vastly higher than even a router in the next room. Unless it happens to >>be right behind the wall but then the user would know that or have to be >>educated about stuff like that. For an AM protocol to work quite well >>you wouldn't need much more than 6dB of SNR above other WLAN participants. > > > yeah! > > If the data was encoded in the lengths of the wifi bursts and the gaps > between them were arbitrary (which they neccesarily would be) it might be > able to work. >Would be really nice but I guess it falls in the "too good to be true" or "there is no free lunch" category. Arlet had hinted that messing with the protocol may be frowned upon by the FCC and that the manufacturers don't let others in on the firmware :-( -- Regards, Joerg http://www.analogconsultants.com
Reply by ●October 29, 20062006-10-29
Hello Jasen,>> >>>>Bluetooth is indeed too complicated. Speed is not an issue as it can be >>>>even slower than 2400bd. Much slower if needed. But simplicity is >>> >>>[...] >>> >>> >>>>Irda would have been nice but this seems to not really have caught on. >>>>None of the laptops I have checked had it. And even there it would >>> >>>[...] >>> >>>I think you probably could send at least a few dozen bits per second >>>via the keyboard num-lock/caps-lock/scroll-lock LED's. I don't know >>>what the API is like in Windows; under Linux, see man setleds >>>and/or source of same. setleds works on virtual term's, not xterms. >>>For xterms, see code at >>>http://www.lugod.org/mailinglists/archives/vox-tech/2005-07/msg00097.html >>> >> >>Now that's an idea. Except that on some laptops (like the Dell here in >>the office) these LEDs are rather dim. > > > or lcds ... >The laptops I had seen with LCD for machine status messaging usually didn't have that little screen backlit. -- Regards, Joerg http://www.analogconsultants.com
Reply by ●October 29, 20062006-10-29
On Sun, 29 Oct 2006 17:20:28 GMT, Joerg <notthisjoergsch@removethispacbell.net> wrote:>Hello Alex, > >>> >>>>The advantage is that it doesn't need a hole, just a translucent section >>>>in the enclosure. >>> >>>I agree, this is a significant advantage. Probably the way to go if you >>>have >>>to be waterproof - you will still be able to make 10 bpS easily, which >>>at your >>>1 - 2 K is still adequate (vs. the 300 bpS of Kansas City). >>>The main disadvantage I see is the necessity to write some modulation >>>software for Windows (yuck). >> >> >> Could always use an ipod screen. >> Make a "music video" that has the correct modulation. >> > >I guess the fact that I don't have an iPod (and never had the desire to >own one...) shows my age ;-)I use it for "books on tape" when I travel... the only time I have to "read" ;-) ...Jim Thompson -- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
Reply by ●October 29, 20062006-10-29
"Joerg" <notthisjoergsch@removethispacbell.net> wrote in message news:wp51h.120$m54.11@newssvr14.news.prodigy.com...> Hello Alex, > >>> >>>>The advantage is that it doesn't need a hole, just a translucent section >>>>in the enclosure. >>> >>>I agree, this is a significant advantage. Probably the way to go if you >>>have >>>to be waterproof - you will still be able to make 10 bpS easily, which >>>at your >>>1 - 2 K is still adequate (vs. the 300 bpS of Kansas City). >>>The main disadvantage I see is the necessity to write some modulation >>>software for Windows (yuck). >> >> >> Could always use an ipod screen. >> Make a "music video" that has the correct modulation. >> > > I guess the fact that I don't have an iPod (and never had the desire to > own one...) shows my age ;-) >Maybe , maybe not :-) Even my mother in her sixties has one (ipod shuffle). They are great for going over lectures , or listening to language "tapes". Plus pod casts of your favourite radio show or similar. Nothing better than sitting back outside on the ferry every morning on the way to work with a good cappuccino and watching the harbour(Sydney) glide past while listening to good music. Alex
Reply by ●October 29, 20062006-10-29
"Joerg" <notthisjoergsch@removethispacbell.net> wrote in message news:0N60h.23275$6S3.11589@newssvr25.news.prodigy.net...> Hello Folks, > > This would address both electronics and embedded engineers. Is there a > method to coax a regular built-in WLAN port on a laptop (or a WLAN card) > into piping out a simple and slow on/off data stream? Without protocols > and all that, and without waiting for any receive packets. > > The reason behind this idea: Assume you have a small uC based product. > Every once in a while it needs to be updated with new firmware. The usual > scenario is to provide a USB connection or an infrared port. Both are > cumbersome. USB adds a lot of cost to the target device and the cable gets > in the way (oh drat, forgot to pack the cable...). Infrared is tough > because many laptops simply don't have it. However, nearly all of them > have built-in wireless these days. >micro sd or mmc card to expensive ? What about wireless usb ? Probably currently to expensive and nothing available (easily) but will get cheaper and more available. Supposedly in some of the current pc chipsets but not enabled. Alex
Reply by ●October 29, 20062006-10-29
Hello Alex,>> >>This would address both electronics and embedded engineers. Is there a >>method to coax a regular built-in WLAN port on a laptop (or a WLAN card) >>into piping out a simple and slow on/off data stream? Without protocols >>and all that, and without waiting for any receive packets. >> >>The reason behind this idea: Assume you have a small uC based product. >>Every once in a while it needs to be updated with new firmware. The usual >>scenario is to provide a USB connection or an infrared port. Both are >>cumbersome. USB adds a lot of cost to the target device and the cable gets >>in the way (oh drat, forgot to pack the cable...). Infrared is tough >>because many laptops simply don't have it. However, nearly all of them >>have built-in wireless these days. > > micro sd or mmc card to expensive ? >Yes, way too expensive here. Plus too much chance for contact failure, ESD, contamination, water intrusion etc.> What about wireless usb ? > Probably currently to expensive and nothing available (easily) > but will get cheaper and more available. > Supposedly in some of the current pc chipsets but not enabled. >Anything that sticks out from a laptop will eventually break in the field. Unsually in the least convenient place (several miles up a dirt road in pouring rain...). Or the USB stick fell out of the tool box but who knows where. -- Regards, Joerg http://www.analogconsultants.com
Reply by ●October 29, 20062006-10-29
Hello Alex,>> >>>>>The advantage is that it doesn't need a hole, just a translucent section >>>>>in the enclosure. >>>> >>>>I agree, this is a significant advantage. Probably the way to go if you >>>>have >>>>to be waterproof - you will still be able to make 10 bpS easily, which >>>>at your >>>>1 - 2 K is still adequate (vs. the 300 bpS of Kansas City). >>>>The main disadvantage I see is the necessity to write some modulation >>>>software for Windows (yuck). >>> >>> >>>Could always use an ipod screen. >>>Make a "music video" that has the correct modulation. >>> >> >>I guess the fact that I don't have an iPod (and never had the desire to >>own one...) shows my age ;-) > > Maybe , maybe not :-) > Even my mother in her sixties has one (ipod shuffle). >Even our president (US) has one, IIRC one of his daughters gave it to him. Don't know about his father though.> They are great for going over lectures , or listening to language "tapes". > Plus pod casts of your favourite radio show or similar. > > Nothing better than sitting back outside on the ferry every morning on the > way to work > with a good cappuccino and watching the harbour(Sydney) glide past while > listening to good music. >My way to work is a hallway, takes about five seconds :-) Except when going to clients but then I have a nice radio and CD player in the car. At airports all the din is too loud anyway. -- Regards, Joerg http://www.analogconsultants.com
Reply by ●October 29, 20062006-10-29
Joerg wrote:> Hello Arlet, > >> >>> Well, that's exactly the point. I'd have to uncouple the WLAN card from >>> it's habit of halting whenever something else talks. At least for a few >>> seconds. However, that might sometimes not be permitted by the >>> authorities. A way around that would be burst transmissions as long as >>> it is legal. Net data rates as low as 2400bps would be quite acceptable. >>> Even less if needed since the user could place the device on the table >>> and then go do something else >> >> >> >> Yes, and the danger of interfering with regulation or the protocol is >> one of the reasons WLAN vendors are not going to let you touch the >> firmware. >> > > That's what I am afraid might stop this approach dead in the tracks. > Unless it could at least be (legally) brought into a burst more where > each burst is interpreted as a bit. > >> >>> The only other option I could think of (and I have done that before) is >>> to provide a photodiode and let the LCD screen flash. However, that is >>> really slow and can annoy others who have to work close to that laptop. >> >> >> >> If you get the photodiode close enough, you only need to flash a small >> area, or maybe you can alternate between colors that appear to have >> similar brightness for human perception, but still offer enough >> contrast for the photodiode. >> > > That would require filtering but could be done. At least it's better > than using audio because that would be really annoying to others. >Hi Joerg, why not take a leaf out of teenagers book of phone tricks, and use 20kHz audio... Cheers Terry
