I recently bought a Stagecoach board and it’s being tested with several Overo FE COM modules.
I followed the tutorial (https://wiki.linaro.org/MichaelHope/Sandbox/StagecoachBringup) to bring it up but failed.
When I plugged an Overo module at the slot closest to the Ethernet port, connected the board to my host PC via the USB console port on Stagecoach, and supplied DC power, only a green LED on the Overo COM was turned on and nothing happened. No LED on Stagecoach was turned on.
When I connected the Overo module (with the same images) to the Robovero expansion board, it was successful: The blue LED on the Overo was turned on and Linux booted.
So I’ve checked the Stagecoach schematic posted on the Gumstix website (http://pubs.gumstix.com/boards/STAGECOACH/PCB30008-R2790/) and compared it with the Stagecoach hardware starting from power circuit.
I found some weird things on my Stagecoach board:
- In the schematic, the voltage selector pins (VS0, VS1, and VS2) of EN5365 (U1) are grounded, meaning that the output voltage should be 3.3V.
- But in the board (hardware), all of those pins are connected to high (5V), and this combination is even not allowed by EN5365 according to the datasheet.
- Eventually, the EN5365 generates 2.07 V to its output port and it directly goes to the Overo modules attached.
The Robovero board supplies 3.3 V to the Overo, so I guess that the power circuit on my Stagecoach has some error.
Do you also think my issue is related to this hardware problem? Or any other suggestions?
Please let me know how to fix this problem.