Monday, March 24, 2008

AT&T Tilt

I have been using a Treo 700p for almost two years now. Verizon replaced my motorola e815 flip phone with the 700p when their forced-upgrade killed bluetooth dialup networking.

My Verizon contract is up and I'm ready for a change. I had considered Sprint for the cheaper data and the possibility of wimax in the next year or so. I decided to go with AT&T for a few reasons...
  • GSM is handy for traveling, use in a laptop, experimenting with my neo1973
  • Using GSM 3G, some phones can do voice and data simultaneously
  • Verizon wireless has been very heavy-handed (It was not fun when they started having billing errors and sending me bills for $2000+)
  • It'll be fun to have a phone with a GPS.
  • I would love to use an iPhone 3G instead, but the SDK can't support background processes and the iPhone won't do DUN or PAN
The tilt is able to do DUN with my n810 and my ubuntu laptop, but it can be tricky.
  • Simultaneous voice and 3G data doesn't work with DUN. This reveals that MS sends the DUN client direct to the GSM chip instead of creating a virtual modem like we have with the bluez dund.
  • I followed the tip to reset the phone when it was counting down to install some extra software. Apparently the extra software disables features.
  • In Ubuntu, I had to log out and run a command like "passkey-agent --default 9876" before firing up DUN. The phone & laptop kept failing to pair when entering a pin using the gnome gui.
  • The internet sharing app DOES allow for simultaneous data and voice (using PAN).
  • The phone delivers data rates up to about 580kbps. *Much* better than the older ppc devices I tried.
  • My neo1973 with original gsm firmware can use this new sim card. It's the first sim I have had success with.

Sunday, March 16, 2008

Dead spider


Nextlink's Spider bluetooth headset is infamous for its failure rate. It's a great headset with a class 1 radio and decent features, but it seems many of them were fitted with lipoly cells that can't hold their charge well. When a lipoly cell runs down below 3.0v, the battery can be permanently damaged so it's a significant problem.

I kept my set plugged in whenever I wasn't using it, but last night it finally went south when the plug came out of the power socket and allowed the battery to drain. After that, the LED would not turn on with any amount of fiddling. I opened it and found the battery, swelled, registered just a touch over 0v on the multimeter. This means it's dead and isn't coming back.

I attached a battery harvested from a helicopter. Now the headset works properly and I don't have to worry about the battery getting too low. It's just not so stylish any more.

Sunday, March 9, 2008

Neo1973: No wifi/3g/battery life? no problem



I decided to rig a better setup for USB host. What I did was open the hub and short the +5v provided to client ports to the +5 on the uplink port. This makes the hub unusable for other purposes, but gives me a nice single-cable solution for a neo hub. I just needed to add a female usb a to mini usb adapter.

The usb device in the picture provides speedy data through verizon cdma/evdo.

I was able to get fastcharge to work on connection. In /etc/udev/rules.d/neohub.rules:

SUBSYSTEM=="usb", ACTION=="add", PRODUCT=="1410/2110/0", RUN+="/etc/udev/scripts/neohub.sh"

and in /etc/udev/scripts/neohub.sh:

#!/bin/sh
echo -n fast_cccv > /sys/devices/platform/s3c2410-i2c/i2c-adapter/i2c-0/0-0008/chgmode

/etc/rcS.d/S98host:

#!/bin/sh
echo host >/sys/devices/platform/s3c2410-ohci/usb_mode

Some issues remain:

  • this would need to be reworked for freerunner
  • there are no decent linux drivers for usb wifi that give us master mode to make an AP