xPC Target

Polling Mode Performance

This is preliminary information. All benchmarks have been executed using a 1 GHz AMD Athlon machine, which is the same machine that is at the top of the list displayed by xpcbench.

The minimum achievable base sample time for model "minimal" (see "help xpcbench") is 1 us with signal logging disabled and 2 us with signal logging enabled.

The minimum achievable base sample time for model "f14" (see "help xpcbench") using an ode4 fixed-step integration algorithm is 4 us with signal logging disabled and 5 us with signal logging enabled.

A more realistic model, which has been benchmarked, is a second-order continuous controller accessing real hardware over two16 bit A/D channels and two 16 bit D/A channels. The analog I/O board used is the fast and low-latency PMC-ADADIO from http://www.generalstandards.com, which is used in conjunction with some recently developed and heavily optimized (lowest latency) xPC Target drivers for this particular board. The minimum achievable base sample time for this model using an ode4 fixed-step integration algorithm is 11 us with signal logging disabled and 12 us with signal logging enabled. This equals a sample rate of almost 100 kHz. The achievable sample time for the same model in interrupt mode is ~28 us or a sample rate of ~33 kHz. For this application, the overall performance increase using polling mode is almost a factor of 3!

Controlling the Target Application

Target PC Command-Line Interface