Z8FS021 Datasheet, PDF (44/68 Pages) Zilog, Inc. – Select from an assortment of lenses and pyroelectric sensors to best fit your application

ZMOTION^® Intrusion Detection
Product Specification
36
Bit
Field
Control
Address
Table 17. PIR Advanced Status/Control Register 0
(ePIR_ASC0)
7
External
V_REF
R/W
6
White
Light
Detected
R/W
5
White
Light
Anti-Jam
R/W
4
3
Buffer
New
Refresh Sample
R/W
R/W
F0H
2
MD
Origin
R
1
0
EM Noise
Detected
EM
Transient
Detected
R/W
R/W
External V_REF (Bit 7)
Select between internal or external V_REF; controlled by the application.
• This bit selects between internal and external V_REF for the ADC when scanning the PIR sensor. When
set to 0, internal V_REF is used and it is automatically set to 1V when the PIR Engine is initialized via
the EPIR_INIT macro. When set to a 1, external V_REF is selected and a regulated 1V signal must be
supplied to this pin by the user. The advantage of using an external V_REF is that it is affected less by
internal operations of the MCU like high drive on an output pin.
0 = Internal V_REF selected.
1 = External V_REF selected.
Note: This register affects the V_REF selection for ADC scans of the PIR sensor only. ADC channel scan requests
made through ePIR SC3 always use an internal 2V reference.
White Light Detected (Bit 6)
White Light Detected on LED; cleared by the application.
• This bit is set by the PIR Engine when a White Light event has been detected. This status is provided
to the user application to indicate that a White Light event has occurred and associated false motion
event(s) may have been suppressed by the Engine. This bit is set by the Engine and must be cleared
by the user application. The threshold or amount of light required to trigger a White Light event is
controlled by the White Light Threshold bits in PIR Status/Control Register 2.
• If White Light detection is disabled (White Light Threshold=00000), this bit is undefined and should
be ignored by the user application.
White Light Anti-Jam (Bit 5)
Stop malicious jamming of the detector via continuous white light events; controlled by the application.
• White Light Anti-Jam is used to prevent a repetitive white light signal from jamming motion detection.
Without Anti-Jam a constant source of white light events can indefinitely inhibit motion detection. With
Anti-Jam enabled, after 12 White Light events within a short duration, the Engine will begin to ignore
them and return to regular motion detection. After a period of no White Light events, the Engine will
begin looking for White Light events again. The feature is intended to prevent malicious jamming of
the detector.
0 = White Light Anti-Jam disabled.
1 = White Light Anti-Jam enabled.
PS028806-0315
Advanced API Register Set