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Issue #204 July 2007
Pyxos Power
by Tom Cantrell
Start | LAN-In-the-Box |Down to the Wire | Variable Interest | Hook 'Em Danno |Build it and they will come | Match point | Sources and PDF
| Function | Description |
| PsInit | This is a user provided (i.e., hardware specific) function called at startup to initialize the SPI the host MCU uses to communicate with the Pyxos FT chip. |
| PyxosPointInit() | Function called at startup to initialize the Pyxos FT chip and API. |
| PyxosPointSendUniqueId() | Each Pyxos FT chip is factory programmed with a unique 48-bit ID that identifies it within the network. In most cases registration is handled automatically by the Pyxos FT chips themselves, but this function allows a Point to manually register with the Pilot if necessary. |
| PyxosPointAnnounceTimeslot() | This function allows a Point to tell the Pilot which timeslot it should be assigned to. Such “hardwired” registration is suitable in networks with a known and unchanging configuration. |
| PyxosPointGetTimeslot() | After initiating registration (either manual, automatic, or hardwired), this function allows a Point to confirm which timeslot it has been assigned by the Pilot. |
| PyxosPointIsOnline() | This function returns true or false to allow a Point to determine that it has successfully registered with the Pilot and the network is operational. |
| PyxosPointEventHandler() | This is the main function that your application must call periodically to handle Pxyos network events. |
| PyxosPointPollPnv() | Though a Pilot, it automatically updates network variables that are inputs to a Point. This function allows a Point to manually check for updates if necessary. |
| PyxosPointUpdatePnv() | This function initiates the transmission of a Point output network variable to the Pilot. |
| PyxosPointIsPnvUpdatePending() | This function returns true or false indicating whether previously initiated outputs from the Point have completed transmission to the Pilot. |
| Table 2—The Pyxos FT network strategy minimizes overhead and complexity for Points, as demonstrated by the simplicity of the Point application program interface (API) leaving the heavy lifting to the Pilot. Compared to the mere 10 functions (many only needed during initialization) that make up the Point API, the Pilot API has nearly two dozen functions. | |
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