Model 1 - Live transmission of text and still imagesHardware chain
Construction NotesFreewaveThe FreeWave transceivers were the first key items I bought. FreeWave seems to be the clear leader in this field. They offer 900 MHz and 2.4 GHz models - the former are more powerful (see their FAQ). I got the `ruggedized' model, but not the water proof one - I may regret this! The units worked straight out of the box, giving a green light to indicate that they were talking to each other.The baud rate needs to be set as per the instructions in the manual. I have had success using the MS Term application, minicom for linux, and ptelnet for the Palm (v 0.53). To get all this working, one needs to get the concept of null modems down. These are simply plastic switch blocks with connectors inside that cross over the send and receive wires of a serial cable. Basically, anything that has been wired to be a `slave' to a computer `master' (e.g., palmpilot, agenda, gps, camera), needs to have its wires crossed when you use it as a master. So the palm and the agenda need null modems in line when they talk to cameras and gpses. They also need a null modem in line when they connect to a computer via the freewave, probably because the freewave sends SND to RCV (i.e. it is itself a null modem, so you have to undo its null-modeming!). If you want to wire your own, see this page. Palm Pilot front end, hotsyncingThe first front-end I tried was a Palm Pilot and PalmPix. This has the advantage of being cheap and easy to use, but the disadvantage of being rather inflexible and hard to network. I did manage to hotsync the Palm over the FreeWave (both to a Windows machine and a linux box with pilot-link), and have PalmPix files transferred, but could only do this at 1,200 Baud - the Palm Hotsync process at higher speeds needs other pins in the 9-pin RS-232 cable that are not joined by the FreeWave.I was also stymied by Kodak who, despite heavy hectoring by myself and others, refused to disclose the format of their PalmPix pictures. The PalmPix images need to be decoded by propriety software as part of the HotSync operation on a Windows or Macintosh system. There are numerous linux users out here who would code up a simple translation script that could help automate the translation and upload process under unix, but Kodak say no. Windows and Mac don't have the capability to be easily automated, so the PalmPix images need to be uploaded to a website by hand. All in all, this approach did not work. The Visor has a camera too, the eyemodule. The original eyemodule had tiny images, but a unix converter was available (eyemodule.py). The eyemodule2 has large, more useful images, but I'm not sure if the eyemodule.py script works with it. Palm front end, modemOne better solution that I have not tried yet is to connect the Palm to a digital camera using PhotoSave (only Olympus cameras supported), then connect to the FreeWave using the PalmModem. The laptop at the other end of the FreeWave would need to act as a PPP server. Alternatively, it may be possible to connect the FreeWave straight to the telephone network, so the PalmModem can call out. PhotoSave allows the JPEGs from the camera to be emailed. Simple annd Neat.Things change rapidly in PalmWare, and I have just found:
Agenda front endThe agenda linux PDA is an amazing tool - a full unix workstation in your palm. Needless to say, it is easier to tweak than the Palm. But, there is a cost - having to learn unix. And the Agenda is a rapidly evolving beta-tool! However, my unit came with a ROM-disk that works well, and I have not had to upgrade the OS yet.The first step is to get your unit talking to your computer. The best resource is Andrej Cedilnik's Agenda pages. Set the link at 57,600 baud on the computer and in the Network viewer app on the Agenda. Download files using rsync. When you are comfortable with this, just add the FreeWave link in between. Set the baud rate to 57,600 (115,200 will also work, but it seems to hang a lot and not be as comfortable). Use a null modem between the FreeWave and the Agenda, and a direct on the other side. Start it all up, and you should be talking. To get photos off a camera, I compiled Salvatore Sanfilippo's s10sh program (for reading the CF of a Canon S10 digital camera) for the Agenda (DOWNLAOD). Drop this (unzipped) onto the agenda, connect the S10 cable to the Agenda cable, via a Null Modem, switch the Canon to Interface, and type ./s10sh. You can also run s10sh in batch mode with the -g switch, to get all images. Garmin etrex GPSThe Garmin etrex puts out a continuous stream of GPS data to its serial port. Go into the Setup -> Interface menu, and set the format to TEXT OUT at 9600 baud. Connect the GPS to your agenda with a Null modem, and type `more /dev/ttyS0'. You should see the data stream. Now `more /dev/ttyS0 > gps' will write that stream to a file . leave it for 5 seconds, then type Ctl-C to escape. The file gps can then be parsed with an awk script I wrote.Finally, use ftp to put the files onto a website. You'll need ftp, and also mawk (for the garmin parser). Get these and all your favourite unix apps at the Agenda Software Repository. Supplies
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