This board has three functions : 1st) translating
USB to TTL Tx and Rx, 2nd) converting USB to I2C and 3rd) supplying
voltage to next board if jumper is between positions 1 and 2.
LEDs are USB activity indicators.
USB Class B is to be connected to desktop/laptop USB
Class A connector. Connector 4x2, P1, is to be connected to
microcontroller's UART using set03_11 cable. Connector 5x2, P2, is to be connected to TWI bus (aka I2C by their inventors, NXP) using set01_04_A cable.
Power supply of this board comes from USB. This
board can be used to supply voltage to boards connected to it (it
relies on jumper's position). Peripherals consumption should respect
set01_05_v3 connected to a
Raspberry Pi using 3Bpi