SBC comparison
Using a service like xPL requires a computer that is always switched on. This poses the question of power consumption and speed.
Comparison
The power consumption has been measured with the SBC running the installed OS with no particular program running.
The delay has been measured by sending a given xPL message which was parsed by the central xPL device on a 300 lines XML rules file. The parsing of the rules is quite lengthy and does not reflect the basic xPL message receiving and sending. Other basic xPL clients who just react on a message and send another one, such as the EIB / KNX interface do this within 0.01 second, even on the slower computers.
| model | Processor | OS | power DC |
delay |
|---|---|---|---|---|
| BeagleBone white | 720MHz ARM Cortex-A8 (AM335x Sitara) | Ubuntu | 0.75 W | 3 s |
| BeagleBone Black | 1GHz ARM® Cortex-A8 (AM335x Sitara) | Ubuntu | 1.5 W | tbd |
| BeagleBone Black with 7" display | Ubuntu | 3 W | ||
| Overo EarthSTORM | 1 GHz ARM Cortex-A8 (AM3703 Sitara) | Voyage | 1.1 W | 0.35 s |
| alix1d | 500 MHz AMD Geode LX | Voyage | 3.75 W | 0.15 s |
| VIA ARTiGO A1000 Pico-ITX | VIA C7 1GHz | Ubuntu | 11 W | 0.1 s |
| VIA ARTiGO A1000 Pico-ITX with lightDM | 11.5 W |
The column power DC provides values that have been displayed by a DC power supply, without the AC adapter.
It is to be noted that bright LEDs consume more then 20 mA, which makes 0.1 W on a 5 V power supply. In other words the LED indicators are a nice feature for the debugging but could be soldered away once the product is functional.
