I was able to power (if not charge) my N900 in USB host mode using a "StarTech 3 feet USB Y Cable for External Hard Drive - Dual USB A to Micro B" cable that I found on http://www.amazon.co.uk/StarTech-fee.../dp/B0047AALS0

I did a test starting with a almost full battery and my N900 connected to a Apple USB-Ethernet adapter and a 1000 mA USB charger connected via the Y cable. My N900 was running x11vnc, WifiEye (WiFi) and Mappero (GPS) and had several active ssh connections. My N900 switched off with an empty battery 345 minutes later. I guess that the N900 was receiving my power from the charger but not enough to power the CPU, GPS, GSM and WiFi.

While this was running, /sys/class/power_supply/bq24150-0/status said "Charging". I'd guess that this is not quite true. The N900 was receiving power but not enough to run the N900 and the battery was emptying. /sys/class/power_supply/bq24150-0/charge_current says "1750". What does that mean? I doubt that it means that the N900 is receiving 1750 mA.

Starting with an empty battery (I charged it just enough to get into USB host mode), I'm now running as before except without x11vnc, WifiEye and Mappero. An hour later the N900 is still alive so it must be getting at least enough power to run if not charge.

I have a 4 questions, when in USB host mode how can I (1) find the current the N900 is currently drawing from the charger, (2) find the current the N900 is currently using, (3) find the battery level, and (4) make the N900 charge at 1000 mA? Looking at https://gitorious.org/rx51-bme-repla...415x_charger.c I guess that I need to write "host" into
/sys/class/power_supply/bq24150-0/mode and then "800" into /sys/class/power_supply/bq24150-0/current_limit. I don't want to write "1000" because then it would charge at 1800 mA (the values seem to rounded up).