Interfacing with Vin-Aux Connector on I/O PCB
Whilst J1 provides the main outward facing power in connections there is a second internal connector (J24) that also provides these same pins
By using this connector we can allow the IO PCB for example to contain a simple UPS circuit (using the 8 way IO connector to take a DC power feed instead of the main 3 way connector) or alternatively with appropriate filtering this connector could be used to create an additional power supply for usage by the IO card where the on-board power supplies have insufficiant capacity.
This diagram below shows the relative location of the connector :
Note that pin 1 (+ve) is on the left hand side, the connector needs to be "placed" on the bottom side