So in the beginning I used 'adb' a lot, and walked over to the TV set in the living room like a million times, asking my wife again and again if it's okay to "borrow" the TV for just a minute and test my latest change(s) ;-)
Now, having the serial console feature, debugging has become so much easier. The console is available early in the kernel boot process, and the device is accessible from my PC. A lot of mistakes you make when customizing the kernel show up on the console, which is very helpful.
This is how I found out that, although no image showed up on my LCD monitor, detaching the monitor was detected by the HDMI driver. This made me think. Could it be a flaw in the HDMI driver after all? All the "solutions" I read about online were related to adding (powered!) splitters, (powered!) repeaters or other converters/adapters to the MK808. In my opinion, one of the nice things of a device like this is that is has an ARM CPU which uses very little power. The succes of having such device 100% working for me would be having a small extremely powerful, "always on" and very low powered device. That's why adding all kinds of additional powered hardware is a real show stopper to me.
Delving into the HDMI device driver code, I looked at the "hotplug" feature. This feature signals any changes on the HDMI port, connecting or disconnecting a display for instance. I changed the code by telling the driver that a display is always connected, in effect disabling the hotplug feature. I also set the resolution fixed to 1280x720 60Hz (
For all of you having the same black screen/no image problem, please try flashing the kernel, and let me know if this fixes the problem for you as well. Included in this 3.0.8+ kernel are a lot of additional patches and changes, cherry picked from the 3.0.50 kernel release. I'll continue to upgrade the kernel to a higher level.
[Update] 2013-01-20 Sound issue fixed.
The kernel can be downloaded here.
[ 21 comments ] ( 16622 views ) | permalink | ( 3 / 2007 )