Connecting the System

How to connect reader boards to the Hub,
and how to connect the Hub to other devices.

Power Supply

You need a 12-18V dc supply, able to deliver 24 Watts (i.e. 12V at 2A).  The connector is a barrel type, with 2.1mm inner, and 5.5mm outer - these are very common.  There are several supplies in the StaRFIshrail store, suitable for worldwide operation, but you may decide to purchase one locally. Note that there is a barrel connector with a 2.5mm, rather than a 2.1mm inner - these may fit, but will give a loose connection - so if you are picking a power supply from your "stock", check the sizing.  It is not recommended to power the hub off your 12V layout bus - this is because a "brown-out" on the layout 12V bus could cause the hub to de-program, requiring a restart of the hub.  The hub is reverse polarity protected, so if you use your own power supply, and have the + and - the wrong way round, no harm will come to the hub - it just won't start!.

Connecting Power

The power entry connector, a 2.1mm/5.5mm barrel, requires 10-20V dc, with a power requirement of 24Watts (to be on the safe side).  This equates to 12V at 2A, or 18V at 1.5A.  Any suitable ac/dc converter can be used.  The incoming dc not only powers the hub board, but all the readers as well.  The centre pin of the barrel connector is positive, and the ring is negative.  The input is reverse polarity protected.
When power is applied, the VIN LED, 4V5 and 3V3 LEDs (all green) should light.  The RUN LED (red) should also flash at approx half second intervals.
You may run this board from your general 12V dc supply, but this is not recommended.

Connecting Readers to Hub

The readers are connected to the hub using RJ45 cables - otherwise known as Ethernet Patch cables.  These can be Cat3, Cat5 or Cat5e - it makes no difference.  Ideally use colour coded cables, this make it much easier to trace the wires if you need to disconnect the hub or the readers.  These cable need to be ethernet "patch" leads - do NOT use crossover leads!.
Make sure that the RJ45 cables "click" home, this ensures good connection, and that they won't drop out!
The RJ45 pinouts follow the Power-Over-Ethernet convention - positive supply is on pins 4 & 5, and negative supply (Ground) is on pins 7 & 8.  The I2C signals are on pins 1&3 (1 being clock, and 3 being data), with pins 2 & 6 also Ground.  Do NOT plug the ethernet cables from the hub into anything but a reader, and do not attempt to plug a reader into anything but a hub - damage may occur!

Connecting between Readers

Quad readers - The quad reader only has one RJ45 connector, and this comes directly from the Hub.
Dual readers  and single readers have two RJ45 connectors.
The dual and single readers can be daisy chained, that is a RJ45 cable is connected from the hub to the first reader, and then another RJ45 cable is connected from the first reader to the second reader, and so on.
On a single daisy chain, there can be two Dual readers, or one Dual reader and two single readers, or four single readers.  The order of the readers on the daisy chain does not matter, but the  readers must be set to different addresses to avoid conflicts. Do NOT put more than 4 RFID points on a single daisy chain - they may appear to work, but they will not work properly. Note that you can also have a daisy chain not fully populated - one dual reader is fine, as is any number up to 4 single readers.
The total length of cable allowed on one daisy chain is 20 metres - this is due to voltage drop on the cable for the power, and capacitance which slows down the I2C connection.  This should be more than enough even for a large layout, provide you have planned properly - but a large layout is likely to have more than 32 RFID points, in which case they should be grouped around different hubs.

Daisy Chaining

2 Dual Readers

Connect Hub to first reader (pink cable) and then first reader to second reader (blue cable).  Make sure the addresses of the two readers are different.

1 Dual Reader, 2 Single Readers

Connect Hub to dual reader (pink cable) and then to single reader (blue cable) and then to another single reader (red cable).  Make sure the addressing is correct.  Readers may be in any order.

4 Single Readers

Connect Hub to first reader (pink cable), then to second reader (green cable), then to third reader (blue cable) then to fourth reader (red cable). Make sure the addressing is correct.

Addressing on a Daisy Chain

The single and dual readers have address switches, and on a single daisy chain these must be set uniquely, so the addressing does not conflict.
In the picture, you can see the various combinations of how the addresses switches can be set. Note that the state of the address switches is locked in by the reader chip on power up - so you need to get the switch position correct, and then re-power the system.  No harm will occur if you get two readers with same address, but the system will not work properly.

Connecting Hub to Ethernet

The primary way of getting data out of the hub, and into a control system computer for using with JMRI or Rocrail, is via Ethernet.  The Ethernet should either be connected directly to your computer via a RJ45 patch cable, or connected through a router.  You can alternatively use a wireless router.  The Ethernet is fixed at 100M.  When the ethernet connection is established, the yellow ETH LED on the hub will light, and the green LED on the ethernet socket will light.  When data is transferred, these LED will flash.

Connecting Hub to CBUS

The hub can be connected to CBUS using the CBUS connector, a 3.5mm 3way plug and socket, consists of + and - and GND connections.  Unlike certain other CBUS modules, the 12V power wire is not required.  The + and - and GND connections are clearly marked on the board.  If you are using a number of hubs on a large layout, use a dedicated CBUS just for the hubs, otherwise the amount of data generated may overwhelm the bus.  The yellow CAN LED will light when there is data on the CBUS - this may be coming from the hub, or may be from other modules on the CBUS. The TERM link terminates the CBUS with 120 ohms - the hub is supplied with this link in. If the hub is not connected to other CBUS modules, you must leave this link in. 

Connecting Hub to USB

The USB connector is a micro B, though generally this will not need to be used.  It is mainly there for programming operations, where you need to update either the firmware or the software.  However, certain settings on the option switch may allow the RFID data to be sent to your computer via USB, rather than via the preferred ethernet connection.

Mounting the Boards

The Hub and Reader boards are supplied with "L" shaped standoffs.  These are attached to the board with M3 6mm bolts.  Also supplied with each board are 4 10mm woodscrews, which are short enough not to protrude through a 9mm baseboard.  The holes in the L shaped standoff can also be used with a M3 bolt and nut.
Mount the board by screwing through the standoffs, which is quite easy, even when working upside down underneath the baseboard.  If you need to remove the board, you can undo the 4 M3 bolts, as the standoffs are threaded.