Design documentation can be found on the eMMC of the board under the documents/hardware directory when connected using the USB cable. Provided there is:
Schematic in PDF
Schematic in OrCAD (Cadence Design Entry CIS 16.3)
PCB Layout (Allegro)
Bill of Material
System Reference Manual (This document).
This directory is not always kept up to date in every SW release due to the frequency of changes of the SW. The best solution is to download the files from http://www.beagleboard.org/distros
We do not track SW revision of what is in the eMMC. SW is tracked separately from the HW due to the frequency of changes which would require massive relabeling of boards due to the frequent SW changes. You should always use the latest SW revision.
To see what SW revision is loaded into the eMMC follow the instructions at https://elinux.org/Beagleboard:Updating_The_Software#Checking_The_Angstrom_Image_Version
It is a good idea to always use the latest software. Instructions for how to update your software to the latest version can be found at:
If you feel your board is defective or has issues, request an RMA by filling out the form at http://beagleboard.org/support/rma . You will need the serial number and revision of the board. The serial numbers and revisions keep moving. Different boards can have different locations depending on when they were made. The following figures show the three locations of the serial and revision number.
Trouble Shooting HDMI Issues¶
Many people are having issues with getting HDMI to work on their TV/Display. Unfortunately, we do not have the resources to buy all the TVs and Monitors on the market today nor go to eBay and buy all of the TVs and monitors made over the last five years to thoroughly test each and every one. We are depending on community members to help us get these tested and information provided on how to get them to work.
One would think that if it worked on a lot of different TVs and monitors it would work on most if not all of them, assuming they meet the specification. However, there are other issues that could also result in these various TVs and monitors not working. The intent is that this page will be useful in navigating some of these issues. As others also find solutions, as long as we know about them, they will be added here as well. For access to the most up to date troubleshooting capabilities, go to the support wiki at http://www.elinux.org/Beagleboard:BeagleBoneBlack_HDMI
The early release of the Software had some issues in the HDMI driver. Be sure and use the latest SW to take advantage of the improvements.
EDID is the way the board requests information from the display and determines all the resolutions that it can support. The driver on the board will then look at these timings and find the highest resolution that is compatible with the board and uses that resolution for the display. For more information on EDID, you can take a look at http://en.wikipedia.org/wiki/Extended_display_identification_data
If the board is not able to read the EDID, for whatever reason, it does not have this information. A few possible reasons for this are:
Cable not plugged in all the way on both ends
Display not powered on. (It should still work powered off, but some displays do not).
DISPLAY SOURCE SELECTION¶
One easy thing to overlook is that you need to select the display source that matches the port you are using on the TV. Some displays may auto select, so you may need to disconnect the other inputs until you are sure the display works with the board.
OUT OF SEQUENCE¶
Sometimes the display and the board can get confused. One way to prevent this is after everything is cabled up and running, you can power cycle the display, with the board still running. You can also try resetting the board and let it reboot to resync with the TV.
Some displays use what is called overscan. This can be seen in TVs and not so much on Monitors. It causes the image to be missing on the edges, such that you cannot see them displayed. Some higher end displays allow you to disable overscan.
Most TVs have a mode that allows you to adjust the image. These are options like Normal, Wide, Zoom, or Fit. Normal seems to be the best option as it does not chop of the edges. The other ones will crop of the edges.
Taking a Nap¶
In some cases the board can come up in a power down/screen save mode. No display will be present. This is due to the board believing that it is asleep. To come out of this, you will need to hit the keyboard or move the mouse.
Once working, the board will time out and go back to sleep again. This can cause the display to go into a power down mode as well. You may need to turn the display back on again. Sometimes, it may take a minute or so for the display to catch up and show the image.
Audio will only work on TV resolutions. This is due to the way the specification was written. Some displays have built in speakers and others require external. Make sure you have a TV resolution and speakers are connected if they are not built in. The SW should default to a TV resolution giving audio support. The HDMI driver should default to the highest audio supported resolution.
If you need some up to date troubleshooting techniques, we have a Wiki set up at http://elinux.org/Beagleboard:BeagleBoneBlack_HDMI