beaglebone-black - Flipbook - Page 13
BeagleBone Black
• Change required PCB revision to B6.
2.2.8 Rev A6
• In random instances there could be a glitch in the SYS_RESETn signal from the processor where the
SYS_RESETn signal was taken high for a momentary amount of time before it was supposed to. To
prevent this, the signal was ORed with the PORZn (Power On reset).
• Noise issues were observed in other design where the clock oscillator was getting hit due to a suspected
issue in ground bounce. A zero ohm resistor was added to connect the OSC_GND to the system ground.
There are no new features added as a result of these changes.
2.2.9 Rev A5C
We were seeing some fallout in production test where we were seeing some jitter on the HDMI display test. It
started showing up on our second production run. R46, R47, R48 were changed to 0 ohm from 33 ohm. R45
was taken from 330 ohm to 22 ohm.
We do not know of any boards that were shipped with this issue as this issue was caught in production test.
No impact on features or functionality resulted from this change.
2.2.10
Rev A5B
There is no operational di昀昀erence between the Rev A5A and the Rev A5B. There were two changes made to
the A5B version.
• Due to complaints about the brightness of the LEDs keeping people awake at night, the LEDs were
dimmed. Resistors were changed from 820 ohms to 4.75K ohms.
• The PCB revision was updated to incorporate the hand mod that was being done on the board during
manufacturing. The resistor was incorporated into the next revision of the PCB.
The highest supported resolution is now listed as 1920x1080@24Hz. This was not a result of any hardware
changes but only updated software. The A5A version also supports this resolution.
2.2.11
Rev A5A
This is the initial production release of the board. We will be tracking changes from this point forward.
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Chapter 2. Change History
