Z8FS021 Datasheet, PDF (35/68 Pages) Zilog, Inc. – Select from an assortment of lenses and pyroelectric sensors to best fit your application

ZMOTION^® Intrusion Detection
Product Specification
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MD Suspend (Bit 4)
Motion Detection Suspend; controlled by the application.
• Temporarily suspends the PIR Engine from running and places it in a very low processing overhead
state and can be used when the application requires significant CPU processing power. While
suspended, motion detection is disabled; however, to ensure fast recovery from this mode, ADC
interrupts still occur and samples continue to be buffered. When the application clears this bit,
suspend mode is exited upon the next ADC interrupt.
0 = Normal Motion Detection.
1 = Suspended Motion Detection.
Motion Direction Control (Bit 3)
Motion Direction Control Enable; controlled by the application.
• This bit enables directional motion detection. The relative direction of the detected motion is indicated
in bit 2 (Motion Direction) of this same register. When configured as a directional detector (bit 3 set
to 1), direction is indicated in bit 2 as a positive or negative relative to the PIR sensor.
0 = Standard Motion Detection Mode. Motion is detected in any direction; the Motion Direction
status bit (Bit 2) is not valid.
1 = Directional Motion Detection Mode. Motion is detected in any direction; relative direction is
indicated via the Motion Direction status bit (Bit 2).
• The directional polarity of PIR sensors is arbitrary at the time of manufacturing. Therefore, it is
necessary for the user application to calibrate to each individual PIR sensor using a controlled target
(i.e. moving in a known direction) and internally recording the polarity to identify which polarity
represents that direction.
Motion Direction (Bit 2)
Relative Direction of Last Motion Detected; controlled by the PIR Engine.
When directional motion detection is enabled, this bit indicates the relative direction of the last motion
detected. When the PIR Engine sets the Motion Detected bit in PIR Status Register 0, this bit is set or
cleared to indicate the direction of the motion. The status is latched until the user application clears the
Motion Detected bit.
0 = Last detected motion was negative.
1 = Last detected motion was positive.
This status bit is undefined when Motion Direction Control is disabled.
Motion Detected (Bit 1)
Motion Detected on PIR Sensor
Set by the PIR Engine; cleared by the application.
This bit indicates that the Engine has detected a motion event. The user application should routinely
check this bit to determine if motion has been detected. This bit is set by the Engine and must be
cleared by the user application.
0 = No motion detected by the Engine.
1 = Motion has been detected by the Engine.
PS028806-0315
Standard API Register Set