AD16 OMNIBUS Module: Sampling Rate

[daniel.hartman]

Greetings all,

I've seen different references for the AD16's sampling rates. In the ChicoPlus help file under AD16, it states that the AD16 can provide data rates up to 192 kHz, while the AD16 datasheet lists a maximum sampling rate of 195 kHz. Although minor, my question is in regard to what happens if you set the sampling rate to a value greater than what an OMNIBUS module supports.

For whatever reason, I was setting the sampling rate to 200 kHz, and although I am very new to this hardware and software development platform, I did not receive any runtime errors. Should I have seen any, or is this type of misconfiguration condition not checked? Everything appeared to run just fine, and I suspect that the actual sampling rate defaulted to the actual maximum sampling rate (192 or 195 kHz), although I have verified this.

Many thanks for the feedback.

Sincerely,

Dan

[jhenderson]

Dan -

The libraries do nothing to enforce use of an acceptable rate. However, within the Pismo libraries, it is possible to query each module to determine its characteristics, including min and max sample rate. We use this technique in order to write generic code for multiple modules. This technique is of less value for those using but a single module type.

In all likelyhood, running a module slightly beyond its specified performance will work ok. However, it is never recommended, since unit-to-unit variations may cause your app to run ok on one platform and fail elsewhere. Also, if you were to scrutinize the AC performance (using a pure sine tone and Binview) of the module run beyond specs, you could see deteriorated performance or rare defects.