Getting Started with the Pyxos FT Platform

What is the development tool for Pyxos?

The Pyxos FT EVK Evaluation Kit is the only development tool you need from Echelon to develop Pyxos based devices or integrate a Pyxos network with control networks based on LonWorks Platform. The Pyxos FT EVK speeds development and includes reference designs for host processors, that you can use with both Pyxos Pilots and Pyxos Points. The EVK also comes with sample application code, source code for the Pyxos FT API, and a sample serial driver.

What types of wire can I use with Pyxos FT networks?

You can use two types of wire:

• Unshielded CAT-5 24 AWG (0.5mm)
• 16 AWG (1.3mm diameter), similar to Belden 8471 cable

For a description of these cables, see the Junction Box and Wiring Guideline engineering bulletin.

Where can I purchase the transformers specified in Pyxos data book?

You can use transformers from Transtek Magnetics; they're available at an approximate price of $0.30 for 10,000 units. For more information, contact:

Part numbers:

Network Isolation Coupling Transformer: Transtek/TMS80040CS
Switchign Power SUpply Transformer: Transtek/TMS60563CS

What are the coupling circuit options for the Pyxos FT chip?

Four network coupling options cover a wide variety of application environments:

• Direct connect (Inside a box, common ground for network nodes, no extra components)
• Non-isolated coupling circuit ($0.03-$0.04 per unit)
• Floating node ($0.03-$0.04 per unit)
• Transformer coupled ($0.33/unit @10,000)

What is the common mode range for the Pyxos FT chip?

• For applications within an enclosure, the differential receiver in the Pyxos FT IC provides rail-to-rail common mode range and may be connected directly to the network with no additional components.
• For network applications where AC mains-based common mode noise may be tens of volts, a simple 4-component coupling circuit provides +/-40V 50/60Hz common mode range -- far better than typical RS-485 transceivers.
• For extremely harsh noise environments, a transformer coupled option provides a common mode range of 277VAC at 50/60Hz and >50Vpp immunity to higher-frequency common mode noise, passing the highest level of EN61000-4-6 conducted RF immunity.

What is link power?

The Pyxos FT network can send both power and data on the same pair of wires. This feature, called link power, eliminates the need for an additional pair of power wires and interface terminals, reducing the cost, size, and complexity of Pyxos FT Points. Link power supports 24VAC or 24VDC and can supply up to 100mA@3.3V for as many as 32 Pyxos Points in the system. The Pyxos Chip data book lists the maximum supported link power distance for both cable types and the number of link power Pyxos Points in the system.

Link power technology is based on technology in Echelon's LPT-11 Link Power Twisted Pair Transceiver.

Reference designs are available for both switching and linear power supplies.