Forcing fast charge mode
This page is intended to consolidate the information about forcing fast charge mode on the Neo.
By default, the Neo will only draw 100 mA of power from a USB connection. If the Neo recognizes the connection as a smart USB connection (by communicating with the host about power availability) or as a standard Neo charger (by recognizing an expected resistance across two of the connectors) then it will switch into 'fast charge mode', drawing 500 mA.
This switch is important, since the Neo almost always draws more than 100 mA to operate (I believe even while it's turned off, since the GSM stays powered up by default), so the battery will actually go dead while the Neo is charging!
There are several ways of forcing fast charge mode:
- From a terminal or ssh session, execute 'echo -n "fast_cccv" > /sys/devices/platform/s3c2410-i2c/i2c-adapter/i2c-0/0-0008/chgmode'
- To add a uboot menu entry, see Bootloader commands
The behaviour is pretty much the same as described above for the Noe 1973. There's also a 1000 mA mode for the OpenMoko-provided wall charger.
See : http://wiki.openmoko.org/wiki/GTA02_sysfs#.2Fsys.2Fdevices.2Fplatform.2Fs3c2440-i2c.2Fi2c-adapter.2Fi2c-0.2F0-0073.2Fforce_usb_limit_dangerous for a description of the "hack" on the register used to control power charge from the FR.
Using a script
I wrote a python script to control the fast charge states.
Power Center allows you to force a Neo Freerunner into Fast charge modes. It can damage your hardware so be careful with what its plugged into. I'm not responsible if you toast the USB port on your brand new laptop.
copy Power Center into /usr/bin and "chmod u+x /usr/bin/power_center"
copy Power Center Desktop fileinto /usr/share/applications
To enable fast 500 mA charge "touch /home/root/allow_force_500"
To enable fast 1000 mA charge "touch /home/root/allow_force_1000" I don't recommend using this one