Hi All, So my company has a datalogger for trucks and etc. It's a simple black box design, nothing too fancy about it. Right now the clients download data by bringing a laptop to the truck, plugging a null modem cable into the RS232 of the black box and downloading the data as a text file via HyperTerminal. We want to make this process easier for our clients. I have the fun task of exploring all the options from CF cards, USB flash drives (Thus my previous post asking how to make a USB driver), blue tooth, RFID, wi-fi and maybe even satellite. I was thinking about using a USB flash drive, have it plug in... auto download and tadda! All done. However, it seems that method is ... more complex than I thought it'd be. I was thinking about using the same approach except replacing the USB flash drive with a CF card. However... before I dive into researching how that would work... I'd like to get the opinions of you guys. Which method would be easiest (aka, fastest and cheapest) to implement? Thanks in advance, Mercy
Best Method to Download Data from a datalogger?
Started by ●October 10, 2006
Reply by ●October 10, 20062006-10-10
On 10 Oct 2006 15:02:01 -0700, "Mercy" <mercy.chang@gmail.com> wrote:>Hi All, > >So my company has a datalogger for trucks and etc. It's a simple black >box design, nothing too fancy about it. Right now the clients download >data by bringing a laptop to the truck, plugging a null modem cable >into the RS232 of the black box and downloading the data as a text file >via HyperTerminal. > >We want to make this process easier for our clients. I have the fun >task of exploring all the options from CF cards, USB flash drives (Thus >my previous post asking how to make a USB driver), blue tooth, RFID, >wi-fi and maybe even satellite. > >I was thinking about using a USB flash drive, have it plug in... auto >download and tadda! All done. However, it seems that method is ... >more complex than I thought it'd be. > >I was thinking about using the same approach except replacing the USB >flash drive with a CF card. However... before I dive into researching >how that would work... I'd like to get the opinions of you guys. > >Which method would be easiest (aka, fastest and cheapest) to implement?A minimum cost + development time option may be to keep the existing application on the black boxes and replace the PC-side Hyperterminal session with a simple app with a Big Red Button that takes care of the serial session and handles some basic sanity checking of the data. A slightly jazzier approach would be to do the above ('cuz NOBODY really likes Hyperterminal) but replace the hardwired serial cable with a couple of 802.15.4 dongles, one on each black box and one on the laptop. Could be taken beyond a simple wired to wireless mod, like a small amount of magic in the dongle cases to allow a unique address per truck. The RF modules are relatively cheap, could be intermixed freely with the existing hardwired serial method (so clients won't need to upgrade all of their vehicles at once), and it could be written to be transparent to the existing blackbox firmware (so no field upgrades required). One option (I'm playing with the dev kit now) are the XBee modules from <http://www.maxstream.net/products/xbee/xbee-oem-rf-module-zigbee.php> -- Rich Webb Norfolk, VA
Reply by ●October 10, 20062006-10-10
Mercy <mercy.chang@gmail.com> wrote:> I was thinking about using the same approach except replacing the USB > flash drive with a CF card. However... before I dive into researching > how that would work... I'd like to get the opinions of you guys.A CF card socket, in a truck? Honestly, I don't think so. You want something a whole lot more rugged than a CF card connector's pins. You want something that the users can clean with a fingernail or a compressed-air hose if something got into the socket that doesn't belong there --- and that still works reliably(!) after such treatment. Just about anything (short of PCMCIA or PCIe cards) would be better than CF there. MMC/SD might be worth a look. There, the biggest risk is that the medium drops on the ground and is washed into the nearest gutter before anyone can bend down to pick it up.> Which method would be easiest (aka, fastest and cheapest) to implement?While think about easiness, don't lose sight of ruggedness. -- Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de) Even if all the snow were burnt, ashes would remain.
Reply by ●October 10, 20062006-10-10
On 10 Oct, in article <1160517721.845877.121300@m73g2000cwd.googlegroups.com> mercy.chang@gmail.com "Mercy" wrote:>Hi All, > >So my company has a datalogger for trucks and etc. It's a simple black >box design, nothing too fancy about it. Right now the clients download >data by bringing a laptop to the truck, plugging a null modem cable >into the RS232 of the black box and downloading the data as a text file >via HyperTerminal. > >We want to make this process easier for our clients. I have the fun >task of exploring all the options from CF cards, USB flash drives (Thus >my previous post asking how to make a USB driver), blue tooth, RFID, >wi-fi and maybe even satellite. > >I was thinking about using a USB flash drive, have it plug in... auto >download and tadda! All done. However, it seems that method is ... >more complex than I thought it'd be. > >I was thinking about using the same approach except replacing the USB >flash drive with a CF card. However... before I dive into researching >how that would work... I'd like to get the opinions of you guys. > >Which method would be easiest (aka, fastest and cheapest) to implement?Fastest and cheapest to implement would be a serial to USB converter ala FTDI232 and other manufacturers, minimal hardware change and load another driver onto the laptop. However note that on some laptops and drivers plugging the USB lead into different sockets SOMETIMES gives different COM port enumerations, which could potentially make it user 'awkward'for running an application. The other method of the Viniculum and similar has already been mentioned but means probably more host software to change how you deal with a file rather than a serial stream. Unless you have two parts of the application already (i.e. download to file and analyse file). -- Paul Carpenter | paul@pcserviceselectronics.co.uk <http://www.pcserviceselectronics.co.uk/> PC Services <http://www.gnuh8.org.uk/> GNU H8 & mailing list info <http://www.badweb.org.uk/> For those web sites you hate
Reply by ●October 10, 20062006-10-10
Mercy wrote:> So my company has a datalogger for trucks and etc. It's a simple black > box design, nothing too fancy about it. Right now the clients download > data by bringing a laptop to the truck, plugging a null modem cable > into the RS232 of the black box and downloading the data as a text file > via HyperTerminal. > > We want to make this process easier for our clients. I have the fun > task of exploring all the options from CF cards, USB flash drives (Thus > my previous post asking how to make a USB driver), blue tooth, RFID, > wi-fi and maybe even satellite. > > I was thinking about using a USB flash drive, have it plug in... auto > download and tadda! All done. However, it seems that method is ... > more complex than I thought it'd be. > > I was thinking about using the same approach except replacing the USB > flash drive with a CF card. However... before I dive into researching > how that would work... I'd like to get the opinions of you guys. > > Which method would be easiest (aka, fastest and cheapest) to implement?As long as you're not the opposition :) I would recommend that the absolute easiest way is not to bring a laptop to the truck. If you use an SD or miniSD under a suitable protective flap (could be magnetic) then all they have to do is pull out the old one and replace it with a blank one. That way there are no magic tricks or recalcitrant microslop laptops to deal with. The pulled cards are simply collected and brought back to the office for processing directly onto a card reader (use FAT16 formatting). If you really want to make the cards rugged or perhaps less fiddly you could mount these into their own mini-module and if you are really keen there would be nothing stopping you from using a cheap micro to interface to the SD and cut down the number of pins needed for a rugged connector. In fact the SD module could look like an I2C device so you would only need 4 pins max. BTW, if your memory requirements aren't all that great you could just use I2C EEPROMs which come in 64KB capacities in 8-pin SOIC. Stack up to 8 of them for more capacity. There is also the RF approach as mentioned but once again it requires a laptop (laptops and truck environments just don't mix). *Peter*
Reply by ●October 11, 20062006-10-11
"Mercy" <mercy.chang@gmail.com> wrote in message news:1160517721.845877.121300@m73g2000cwd.googlegroups.com...> Hi All, > > So my company has a datalogger for trucks and etc. It's a simple > black > box design, nothing too fancy about it. Right now the clients > download > data by bringing a laptop to the truck, plugging a null modem cable > into the RS232 of the black box and downloading the data as a text > file > via HyperTerminal. > > We want to make this process easier for our clients. I have the fun > task of exploring all the options from CF cards, USB flash drives > (Thus > my previous post asking how to make a USB driver), blue tooth, RFID, > wi-fi and maybe even satellite. > > I was thinking about using a USB flash drive, have it plug in... auto > download and tadda! All done. However, it seems that method is ... > more complex than I thought it'd be. > > I was thinking about using the same approach except replacing the USB > flash drive with a CF card. However... before I dive into researching > how that would work... I'd like to get the opinions of you guys. > > Which method would be easiest (aka, fastest and cheapest) to > implement? > > Thanks in advance, > MercyI had a very similar problem with an industrial boiler control where the old method was to use a laptop with an IrDA dongle to transfer data. I started a thread on it about a year ago called "Upload Options" or similar but I can't find it in google. I went through the various option and, because I have a big chunk of data to shift (16Mb), then I decided to go the MMC route and have been pleased with my choice. If you don't have much data and can handle a bit of extra cost and some IT issues then BlueTooth could be a sensible method but you could be faced with a row of ten trucks all claiming to be truck number 1 and no way easy way to tell them apart. However, this is an implementation issue not a design problem. MMC is cheap as chips (with small cards) and has no licensing issues which is one of the things that appealed to me. Bear in mind that, if the cards are accessible from outside the vehicle then kids will find out and steal them. Don't put it past the drivers not to "borrow" them for their digital cameras either. I have designed my system not to start up without a card in it so anyone pinching them will have a lot of explaining to do when the boilers don't start up!
Reply by ●October 11, 20062006-10-11
Mercy wrote:> So my company has a datalogger for trucks and etc. It's a simple black > box design, nothing too fancy about it. Right now the clients download > data by bringing a laptop to the truck, plugging a null modem cable > into the RS232 of the black box and downloading the data as a text file > via HyperTerminal. > > We want to make this process easier for our clients. I have the fun > task of exploring all the options from CF cards, USB flash drives (Thus > my previous post asking how to make a USB driver), blue tooth, RFID, > wi-fi and maybe even satellite.Something else you may want to consider in your decision is whether to use a FAT filesystem on your data card or not. If the clients could pull out the data card at any random time, or if the system could ever reset due to insufficient power (e.g. when starting the car in cold weather on weak batteries), a FAT filesystem can easily be corrupted. A standard card with a standard FAT filesystem might also be tampered with by the driver, in order to destroy any evidence of bad behaviour (this may not apply in your case) A journalling filesystem could be made more robust against such interruptions.You could upload the new data in an unused part of the flash, then verify it, and mark it valid. If this process was interrupted, simply find the same spot, and try it again.
Reply by ●October 11, 20062006-10-11
Mercy wrote:> So my company has a datalogger for trucks and etc. It's a simple black > box design, nothing too fancy about it. Right now the clients download > data by bringing a laptop to the truckDo your users a favor and use ZigBee. They'll be happy if there's no wire to plugin.
Reply by ●October 11, 20062006-10-11
Eric wrote:> Do your users a favor and use ZigBee. They'll be happy if there's no > wire to plugin.Got a hammer in your hand, and looking for nails, eh? He merely has to add an RF module and wait for the rest of the universe to support ZigBee. Automotive environments are fairly RF hostile, too. Removable flash media is the right thing to do here. Your solution sounds rather like the ultimate sort algorithm, which can sort an arbitrary number of items in linear time: Distribute the items randomly. In at least one parallel universe, this must result in a perfect sort. That is the only universe you care about. So the algorithm is: Distribute items randomly. Check if they are sorted. If not, destroy the universe.
Reply by ●October 11, 20062006-10-11
larwe wrote:> Eric wrote: > > Do your users a favor and use ZigBee. They'll be happy if there's no > > wire to plugin. > > Got a hammer in your hand, and looking for nails, eh? He merely has to > add an RF module and wait for the rest of the universe to support > ZigBee.Agree, ZigBee is overkill.> Automotive environments are fairly RF hostile, too.GPS, CB and Plain Old Radio are RF too, but you do need to plan your EMI and antenna.> Removable flash media is the right thing to do here.Or a removable module with RF and Flash. I would look into the ISM band (434 MHz) RF transceiver, they can go upto 200K Baud in theory. In particular, we are looking into the TDA5100/5210 or TRF6903 for such application. FSK should have better noise immunity for auto environment.