Age | Commit message (Collapse) | Author |
|
The idea of the red LED used to be to indicate power delivery to the
board independent of firmware.
While this is good to know it adds the constraint that even without
firmware the LED should light up. Furthermore it should stop lighting up
when the firmware takes over the blinking with different colors. This
was solved with a NOT gate.
This adds more parts to the assembly at the cost of rare space. To
reduce space consumption this feature is removed.
The effect is that the user cannot distinguish anymore if the board has
an issue with power supply or with not running firmware. This is
acceptable because the user cannot do anything about both issues.
Developers have the chance to e.g. connect the UART to validate if the
firmware is running.
|
|
|
|
|
|
|
|
|
|
Making them active-low makes it easier to reset the MCU. For the wipe
functionality it does not make a role since it will simply be defined in
Devicetree.
|
|
This voltage divider provides an analog voltage between GND and +3.3V to
indicate which hardware revision this board is.
Thus the same firmware image can be used on multiple PCB versions
compensating the hardware differences in software.
The resistor combinations are calculated by
`tools/resistory_selector.py`.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|