1.9 KiB
Test DSI and HDMI Display
The Discovery Kit 1 has a HDMI output, while the Discovery Kit 2 has
both HDMI output and a DSI panel. The demo configurations include
the modetest utility, which allows low-level testing of display
devices, directly by using DRM devices.
First you can run modetest -c to enumerate the connectors available
on your system. On the Discovery Kit 2, the output looks like this:
# modetest -c
...
Connectors:
id encoder status name size (mm) modes encoders
32 0 connected HDMI-A-1 480x270 5 31
modes:
index name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot
#0 1280x720 60.00 1280 1390 1430 1650 720 725 730 750 74250 flags: phsync, pvsync; type: driver
#1 1280x720 50.00 1280 1720 1760 1980 720 725 730 750 74250 flags: phsync, pvsync; type: driver
#2 800x600 75.00 800 816 896 1056 600 601 604 625 49500 flags: phsync, pvsync; type: driver
#3 720x576 50.00 720 732 796 864 576 581 586 625 27000 flags: nhsync, nvsync; type: driver
#4 720x480 59.94 720 736 798 858 480 489 495 525 27000 flags: nhsync, nvsync; type: driver
...
34 0 connected DSI-1 52x86 1 33
modes:
index name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot
#0 480x800 50.00 480 578 610 708 800 815 825 839 29700 flags: ; type: preferred, driver
So we can see that we have two connectors: connector 32 is the HDMI
output, while connector 34 is the DSI panel. Obviously, on the DK1,
the connector corresponding to the DSI panel will not be available.
You can then test the HDMI output by displaying modetest default
picture, for example in a 720p resolution:
# modetest -s 32:1280x720
You can test the DSI output by displaying the same modetest default
picture, in the native DSI panel resolution:
# modetest -s 34:480x800