Error Threshold

The error threshold specifies the maximum conversion result allowed for any element within a sensor. Error threshold crossings are detected in hardware. If during the conversion process one or more elements does not complete their conversion before the conversion result crosses the error threshold, the peripheral will terminate the conversion and the error condition will be flagged in software at a sensor level. This mechanism prevents a conversion from continuing forever in the event of an incorrect calibration or a hardware problem. Hardware problems may include, but are not limited to, a disconnected electrode or a shorted electrode. The figure below illustrates an error threshold crossing. Note that the conversion result never exceeds the error threshold, as the CapTIvate peripheral stops the conversion upon crossing of the error threshold. Unlike other thresholds, the error threshold is an absolute threshold, and is not relative to the LTA.

Implementation Notes
Conversion results are 13-bit values. As such, the maximum conversion result as well as the maximum error threshold is 8191. This is the default error threshold, and is fine for most applications. However, the error threshold may be reduced here if desired. Lowering the error threshold limits how long the peripheral may continue trying to complete the conversion. It is up to the application to determine how to handle an error condition in software. Several steps may be taken to determine why the error condition occurred, such as a re-calibration or a self-test.

Range of Valid Values for the Error Threshold Parameter
The error threshold may be set from 0 to 8191. Conversions are limited in hardware to a maximum result of 8191.

Affected Software Parameters
The Error_Threshold parameter corresponds to the ui16ErrorThreshold member of the tSensor type in the CapTIvate Touch Library.
If an error condition occurs at runtime, the bMaxCountError member of the affected tSensor instance will be set to alert the application that there was an error in the conversion.