WTNet

WTNet is an idea for controlling large scale outdoor railroading.

WTNet is based on the Walkie-Talkie technique with one master, Rocrail, using the CBUS protocol.

• Reduce field wiring.
  If the outdoor layout already uses DCC on the tracks this WTNet can be used for sensor reporting by the loco itself by RFID-Tags under the tracks; No need for detection sections or Reed contacts.

This is the train controller with the following features:

• 200Hz duty-cycle Motor control.
• 8 function outputs.
• RFID reader connection.
• 22000µF power buffer.

The tracks are expected to deliver at least 16V and enough power.

The CAN-GCrf is protocol compatible with the CAN-GC3 which make it possible to use the CANCAB too for controlling the locomotives.

The CAN-GCLN makes it possible to use LocoNet throttles like FRED's.

Rocrail connects to the CBUS by the CAN-GC1e ethernet TCP/IP interface.

andRoc can be used as usual with its rich range of possibilities.

1. A RFID reader for scanning RFID-Tags.
2. A tranceiver unit.
3. A PIC based controller: GCrf.

1. A tranceiver unit.
2. A PIC based controller:
   • Communicates with the tranceiver over SPI.
   • CAN interface. (CBUS)

The master supports the same CBUS opcodes as the CANCMD/CAN-GC3.

1. The master send subsequently commands to every known loco in the system.
2. It will switch to receive mode and wait for a response from the addressed loco.
   • This response may include sensor information like magnet or RFID-Tag.
3. After the response is processed, or a timeout occurred, the next loco is send a command → goto 2.

The command packet include a loco address.
All locos are by default in receive mode and will only process commands matching its own address.

• Microchip MRF24J40MA radio transceiver module
  • Data sheet
  • MRF24J40 Radio Utility Driver Program
    • mrf24j40-radiodriver.zip Source code
  • 802.15.2-2003.pdf IEEE 802.15.2-2003