wiki/ news/ 2012-02-21 - More mucking with SMBUS on the new FC

So we tried all this again, and this time added a BQ24725 battery charger IC evaluation board to the kit. And some real batteries! Albeit small ones.

Part 1: Build, Josh, build!

After finding a really obnoxiously recent patch to the sbs-battery module, Josh heroically built us a 3.3.0-rc4 kernel and installed it on the CF card! And it booted! But then....

Part 2: Oh woe! Josh left us! Go back to old things.

Gah, we forgot to include the e1000e module so we couldn't connect to the interwebs. Bah. Jamey's too lazy to build a new kernel, so we booted the live USB key from last time. Lo and behold, we saw the charger chip at chip address 0x09 on the SMBUS. Hooray!

Running sudo i2cdump -y 0 9 gave us the memory dump, and the last two bytes were 0x40 0x08 which is sweet since the data sheet says

REGISTER ADDRESS REGISTER NAME READ/WRITE DESCRIPTION POR STATE
0XFEH ManufacturerID() Read Only Manufacturer ID 0x0040H
0xFFH DeviceID() Read Only Device ID 0x0008H

Woot!

Next, we read the status from the BQ3060 to make sure it was happy:

Part 3: Talking to the BQ24725 and charging batteries

First we played around:

Eventually, we got it to charge!:

To prove that we were charging, we asked the BQ3060 sudo i2cget -y 0xb 0 w and it sat 0x050a which is "I'm charging!".

Double w00t.