Z8FS040 Datasheet, PDF (25/56 Pages) Zilog, Inc. – ZMOTION Detection and Control Family Featuring Zilog’s PIR Technology

ZMOTION^TM Detection and Control Family
Product Specification
PIR Engine Enable Register (ePIR_Enable)
Bit
7
6
5
4
3
2
1
0
Field
Control
Address
PIR Enable/Disable Pattern
Read/Write
100H
PIR Enable/Disable Pattern (Bits 0-7)
PIR Enable/Disable Register
Controlled by Application
The PIR Enable Register controls the overall operation of the PIR engine. As an added level of
protection, there is a specific 8 bit enable value and 8 bit disable value. All other values are reserved.
Reading this register returns the last value written. Once enabled, the PIR engine reads the application
controlled Status/Control Register values and sets the engine controlled values to their default state.
To enable the PIR engine, first write the ePIR_ENABLE_PATTERN to the PIR Enable Register then
execute the EPIR_INIT macro.
Pattern
Name
00h
ePIR_DISABLE_PATTERN
11h
ePIR_ENABLE_PATTERN
Table 6 - PIR Software Enable Patterns
Description
Disables all Engine functions, including motion detection.
Used to temporarily or permanently shut down the engine.
Enables the PIR engine. All primary engine functions as
configured in Engine Status/Control Registers are enabled.
Confirmation of enabled status is provided through Engine
Disabled bit in Status/Control Register 0.
PIR Sensitivity Register (ePIR_Sensitivity)
Bit
7
6
5
4
3
2
1
0
Field
Sensitivity
Default
U
U
U
U
U
U
U
U
Control
Read/Write
Address
101H
Sensitivity (Bits 0-7)
PIR Sensitivity Setting
Controlled by Application
The PIR Sensitivity Register is used to adjust the sensitivity of the PIR engine to target motion. Lower
values produce higher sensitivity to motion with 00h being the most sensitive and FFh being the least
sensitive. The user application should load this register with the appropriate value to give the desired
sensitivity.
Notes:
 The setting of this register also affects the range of detection. Lower values increase range and
higher values decrease range.
 Depending on the lens and pyroelectric sensor used, values above 3Fh may result in very limited
detection.
PS028506-1110
PRELIMINARY
20