C3e-mb-pcb-v4 !new! -

One clever addition in V4 is a 2-bit hardware revision strapping. Four resistors on the bottom layer pull two GPIOs (IO4, IO5) high or low.

If you are replacing an older with the V4 , you need to know why the upgrade is mandatory for specific use cases. c3e-mb-pcb-v4

If you are looking for "POST" information (Power-On Self-Test) because the board isn't starting: For the Multiplexer: One clever addition in V4 is a 2-bit