Technical data

www.asti-usa.com ASTi DACS: Operation & Maintenance Manual (Version 4, Rev. B.1)

Processor Loading

There are two types of processors in an ASTi DACS - the model processor, which has a Pentium

or other X86 microprocessor, and the DSP processors. There is one DSP processor on each DSP

card.

Both the Model Processor (or CPU) and the DSP processors can only handle a certain amount of

information before they can no longer keep up with the simulation. Different tasks load these pro-

cessors in varying amounts. Some tasks consume a lot of DSP processing, but very little CPU pro-

cessing. Conversely, some tasks eat up CPU processing while using very little DSP time.

The following table lists the relative loading effects of various objects on the DSP and model pro-

cessors.

In general, objects that mix large numbers of sounds (like mixers and Comm Select Panels) use a

lot of DSP processing, while objects that require a lot of modeling (such as computing radio rang-

ing effects) use a lot of CPU processing.

Generating signals (such as tones and aural cue sounds) uses DSP time, as does ﬁltering sounds.

Increasing sound ﬁdelity by increasing the sound sampling rate also loads the DSP, by giving it

more samples to generate and manipulate in the same amount of time.

Anything that forces the CPU to handle sound directly (recording and playing sounds, and DIS),

uses up a lot of CPU time.

Table 1: Processing Loads of Different Objects

Object CPU Loading DSP Loading

Mixer Object Low High

Radio Object High Medium

Comm Select Panel High Medium

Control Objects Medium None

Recorded Sounds High Medium

Intercom Bus Low High