The HDMI port on HiKey supports TVs and monitors with an HDMI interface at display resolutions from 1920x1080 (or 1920x1200) pixels down to 640x480 pixels. Note that interlaced display modes are not currently supported. The mobile SoC used on the HiKey board does not have sufficiently flexible clocking arrangements to support all possible HDMI timings specified by monitors. A list of monitors/TVs can/cannot work with HiKey is stored here.
Note also that these modes are preferred and will be tried (in this order) first if they exist in EDID:
The Debian build uses Linux DRM drivers for the graphics system. When first powered up the board, it will attempt to read the EDID display data from the attached TV/monitor. Then it will select the highest resolution format available up to 1920x1080 pixels. If the setting is well selected, the default format will work for your TV/monitor and no more needs to modify anything. However, in some cases, the TV/monitor may not display correctly using the selected setting, because the timing is not exactly correct. In this case, we have provided a facility to enable you to cycle through the available EDID modes to find one that works correctly for your TV/monitor.
After the board has booted the User0 LED should be heartbeating about once per second. To cycle through the available EDID modes, we're using the following key sequence Right_Alt + PrintScr + G to do so:
Press the right hand Alt Key then the PrintScr key and then the G key so that finally all the keys are pressed. Each time you enter this key sequence the HiKey will switch to the next available screen mode. When you find one that works well, please write down the corresponding resolution and frequency you obtained from the TV/monitor display - for example, 1280x1024@75Hz.
If at last we still have difficulties, we can revert to a built-in 720p mode by starting up the HiKey with no HDMI device attached. The UI will then come up at a fixed 1280x720 resolution which will be used when you then plug in the HDMI monitor. Press hotkey Right_Alt + PrintScr + G will switch to a built-in 800x600 mode; again, we can then cycle back.
[Information on Android To Be Written]
At the moment resolution is locked to 1280x720p.(here we do not use the hotkey Right_Alt + PrintScr + G).
Note: the fixed settings may not work on all TV/monitors but have been tested to work on most of them.