Hi,
On Thu, Sep 11, 2014 at 3:05 PM, Dr. H. Nikolaus Schaller hns@goldelico.com wrote:
here a short update of the hardware test results (the 3.17 kernel git is updated accordingly trying to make things work).
First, let's start with what has already been tested and is working fine:
• Keyboard-Backlight LEDs • Shoulder Buttons • Nub buttons • Nubs (Position etc.) • Keyboard • Sensor: BMP180 (digital barometric pressure sensor) • DC/DC-Converter for the USB-Hosts ports • magnetic lid detector
Not yet tested:
• RGB-LEDs
have been fixed (hardware issue). Just one flaw: the red LEDs glow a little even if turned off. We need to rewrite the tca6424 driver so that gpios can be configured as "open drain" outputs: http://projects.goldelico.com/p/gta04-kernel/issues/658/
I hope such setup doesn't waste power..
• Stresstest VBUS
the vbus voltage breaks down at ~11 Ohm load which means 450 mA. This is a little lower than expected and required (should be at least 500 mA - better 1A). vbus can be turned on/off through GPIOs. The next version of the main board will indicate over-current (either through red LEDs and/or GPIOs)
We had lots of issues with this on pandora, some of which were never resolved. First MWeston found that some rotational USB drives use excessive current while spinning up, > 1A. Pandora can do a bit over 1A, but still there were reports on the forum that some drives don't start up without powered hub. Not much can be done about that I guess, but still I think we need to be able to supply at least something close to 1A and surely not 450mA.
Then there was an issue that the LCD was powered from the same power supply as VBUS, and connecting a drive would make the backlight flicker wildly, so we need a dedicated supply (maybe it already is in your design, I don't know how to check).
Later it was found that overcurrent protection doesn't actually work. I'm not sure if it was ever fixed.. There was even report of a burned board from USB HDD user. The LCD got it's own supply for rebirth.
Last and most annoying thing is that turning off VBUS over GPIO on pandora wastes more power than the whole OMAP3 with LCD off (no idea why), so we never turn off VBUS on pandora.
I really hope it will all work properly this time..
• Microphone-Detect-Switch
the TS3A225E works fine if accessed through I2C. A new test script is here: http://git.openpandora.org/cgi-bin/gitweb.cgi?p=pyra-kernel.git;a=commit;h=3... It even sends the mic_present signal to the TCA6424 which even raises the INT GPIO (can be checked by exporting it and reading from /sys). But the kernel does not handle changes as IRQ and they don't arrive in the extcon-gpio driver as expected.
• CPU-Reset-Logic (LSH-BOTTOM + Poweron)
this circuit is broken and needs to be redesigned.
• Charger-Bypass
works (except some insignificant issue which can be solved later - if at all).
Could you explain what that is? Powering the device without battery perhaps?
• FTDI232 (Linux console)
responds on the USB side.
Again, I hope it doesn't waste power..
• Charger
the charger chip behaves sane and expected (as far as it could be tested without real battery and system consuming high energy). A preliminary I2C driver for the bq2429x has been added. But the charger should also work without driver.
• Vibration motor, Microphone, Speakers
not yet tested.
• Modem-USB, Modem-Ignite, GPS
not yet tested (was already tested in the previous design except GPS and new functions like new SIM card reader).
• INA231 (for checking modem status/power)
a hardware issue prevents complete test.
• Fuel Gauge(s)
bq27200 responds but delivers unreasonable values. bq27421 does not respond.
• Other sensors
With pandora experience I feel uneasy with all these sensors.. I hope they all can be turned off or have good power management states, as on pandora nubs can't be turned off without wasting lots of power, again for unknown reasons..
Can't be tested yet (as we need the CPU-Board and/or the next revision of the motherboard: • HDMI • eSATA • USB-OTG 2/3 • Audio • WLAN/BT
I guess audio is still to be selected, like BT/WLAN?
• Display connected to the mainboard
More tests to be done beginning of next week. And I have not yet continued to develop/test the Displays.
BR, Nikolaus