Z8FS021 Datasheet, PDF (21/68 Pages) Zilog, Inc. – Select from an assortment of lenses and pyroelectric sensors to best fit your application

ZMOTION^® Intrusion Detection
Product Specification
13
Low Power Op Amp
Comparator
UART
Temperature Sensor
LED Drive
WDT
Table 3. Peripheral Availability (Continued)
Not Available
Not Available
Available to application. Available to application.
Available to application – Available to application.
No CTS.
Not available.
Not available.
—
Available to application.
Available to application. Available to application.
Not Available
Available to application.
Available to application.
Not available.
Available to application.
Available to application.
The remainder of this section further describes the differences in application availability
between the 8-pin, 20-pin and 28-pin peripheral sets.
Analog to Digital Signal Conversion
Zilog’s PIR technology requires exclusive access to the ADC peripheral to detect motion.
However, ADC conversions can be requested by the application via the API (PIR Status/
Control Register 3). If it is necessary for the user application to utilize the ADC peripheral
directly, the PIR Engine must first be disabled via the PIR Engine Enable Register in the
API. Motion detection is not possible while the PIR Engine is disabled. When the user
application is finished with the ADC peripheral, it must reenable the PIR Engine.
8-Pin Device. PA3 (ANA2) is reserved as the analog ADC input from the pyroelectric
sensor. Therefore, ANA2 is not available for user applications. Additionally, ANA3 is
used for a second sensor input in Dual Pyro Mode. All other channels are available to the
user application.
ADC Channel
0
1
2
3
Available to Application
Yes
Yes – used for White Light detection
No
Only in Single Pyro Mode
20-Pin Device. PB2 (ANA2) is reserved as the analog ADC input from the pyroelectric
sensor. Therefore, ANA2 is not available for user applications. Additionally, ANA3 and
ANA6 are not available because PB3 (ANA3) must be tied directly to PC2 (ANA6/
V_REF). PC2 is configured as V_REF output by the PIR Engine. In Dual Pyro Mode, ANA3
is used for a second sensor input rather than being tied to V_REF; ANA6/V_REF therefore
becomes available. All other channels are available to the user application.
PS028806-0315
Peripherals