By default the TomTom One doesn’t give console access over ttySAC0, instead it looks like a plug & play daemon periodically polls the port possibly for a GPRS modem. A few attempts at allowing access to the shell with TomTom Navigator running concurrently failed so rather than modifying the ttpnpd file that I use to launch my main application I created a file called SerialTTY.cap in the SDKRegistry directory:
Version|100| AppName|SerialTTY| AppPath|/mnt/sdcard/bin/| AppIconFile|tty.bmp| AppMainTitle|Serial TTY| AppPort|2001| COMMAND|CMD|cmd|tty.bmp|SerialTTY|
And in the bin directory created a small shell script called SerialTTY to perform the redirection between the shell and the /dev/ttySAC0 port:
#!/bin/sh
cd /mnt/sdcard
stty -F /dev/ttySAC0 115200
sh < /dev/ttySAC0 > /dev/ttySAC0 2>&1
All works well and after the initial period I didn’t see any more interference from the plug & play daemon. I noticed in the /bin directory (on the internal filesystem) that the lrz binary is provided and successfully used it to perform a zmodem file transfer. In conjunction with a few scripts this may be a more convenient way to transfer new binary images to the device rather than going through the reboot required when using the USB mass storage interface.
Here is some more information
http://lists.gnumonks.org/pipermail/opentom/2006-August/000288.html
It turned out that in 910 the plug&play daemon takes over /dev/ttyS0
by default.
Placing the following script as ‘TTPnPD’ to the sdcard or hard disk
root gives a shell nicely.
#!/bin/sh
exec /dev/ttySAC0 2>&1
stty 115200
while true; do
sh
done
Kudos to TomTom Pro service for allowing me to figure this out this
fast!
Hi Peter
Do you access the console of tomtom one v3 via usb-plug (or did you do some welding on tomtom`s board to get a seriel port)?
I “only” want to use it as gps-reciver, is there a chance without modifying the device?
My tt1 v3 has no sd-slot and no BT. Only powerbutton, reset, antennaconnection and usb. Over the usbconnection I can use it only as storage-device and the directories and files on it don`t look like a linux OS.
I loaded the cdc-acm-module and tryed to connect the tt from terminal (that works fine with a mobile as modem)…I know it not a modem:) You see I`m walking in the dark and would be happy for some hints.
greetings
Hi Steff, I modified the board, as you’ve found the USB only works as a mass storage class by default. I’m guessing what you’re calling the antenna connection is the connection for accesories such as the traffic data receiver and looks a bit like a microphone jack? If so you can get at the serial port over that, see the post http://blog.peter-johnson.com.au/?p=49, however I couldn’t find a source for the connectors which is why I pulled my unit apart and added the different lead. I noticed somone has posted a hint about using old iPod interfaces to get the connector, although you’d need to buy a TTL to serial converter and still do a bit of soldering.
It’s been a while since I looked at it but I don’t think the kernel supports CDC so I can’t really think of any way to acheive it without using the serial port. I guess you’re trying to save a few bucks but I found the output from the receiver to be somewhat bursty and I don’t think the hardware / software GPS receiver the V3 receiver uses is quite as a good as a SiRF III or UBlox receiver. It might be worth shelling out for a USB GPS receiver now they are only around $50.
Hi Peter, I send a message some days ago, but it did not work. However, i wanted to thank you for the fast reply and yes you are all right, I want to save some bucks, but it´s not only that. If I have a device that does already a job, I´m very interested trying to use it allround (but not with the TT, I need it and will follow your advice).
And thanks for the link with the mac-plug. If I find one I will try it out. I already soldered a TTL-adapter ( very proud:)), that I needed to play open-nas software(very good howto) on a allnet6200 with broken firmware (a friend of mine found it on the rubbish).
You have a very nice page – thank you steff