Using the same STM32F405RTG6 processor as the Cerbuino on a custom board, I am finding that PA9 is always low when I read it.
I have the weak pullup enabled and reading with a meter the pin is 1.1V and all the others are 3.3V as expected.
On the original Cerbuino this is marked as VBUS but there is no physical connection to the USB port.
Any reason why it won’t pullup to 3.3V?
Works as expected here 
Strange. Both boards are exhibiting the same 1.1V reading when enabled as INPUT with PULLUP enabled.
Is that test on your board with the original Cerbuino firmware?
The highlighted track is the one in question. Not shorted to GND either. High impedance on the meter to ground.
NETMF 4.4
I only have 4.38 for it.
Well if you wanna play in the cool NETMF sandpit…
I have used 4.4 with your nice little boards but sadly, the Cerbuino is only available with 4.38 firmware.
Zoom in on the STM - looks like a 405 to me 
Ok smarty pants, where can I get the firmware to program this with that is compatible with the Cerbuino Bee?
Can spit you out a firmware in the morning if you want…
That would be very nice of you, young man.
I should be able to just switch to 4.4 and recompile.
