GY-63_MS5611/libraries/PIR/README.md

PIR

PIR library for Arduino. Supports up to 8 PIR sensors.

Description

The PIR library implements a class to monitor 1 or more PIR sensors. The library supports up to 8 PIR sensors per object, which typically are added in setup(). It is possible to add a sensor (pin) multiple times. The library accepts duplicates.

The library has two read() functions, one to read a specific sensor, and one to read all of them. The latter will return a mask indicating HIGH and LOW. The first added PIR will have the LSB.

Instead of PIR sensors one can add other DigitalOut sensors or even switches.

Interface

Base

• PIR() constructor. Allocated room for 8 PIRs.
• uint8_t add(uint8_t pin) adds a PIR pin to the set of pins. Returns the index or PIR_ARRAY_FULL (0xFE)
• uint8_t count returns number of PIR sensors added.

Read

• uint8_t read() read all PIR sensors in the set. Returns a bit mask of HIGH / LOW values. Not used slots will return 0.
• uint8_t read(uint8_t index) read a specific PIR sensor. Faster than read() above.
• uint8_t lastValue() returns last values read (bit mask) with read().
• uint8_t changed() returns bit mask of pins that changed since last read(). This can improve processing in some cases.

Future

Must

• update documentation

Should

• add examples
  • interrupts?

Could

• investigate PIR16 PIR32 class that can hold more
  • think MEGA2560.
  • or dynamic allocation? 0.2.0
• one lastRead for all?
• uint8_t pin(uint8_t index) to get back configuration
• bool add(uint8_t array, length) faster configuration. Return true if there was enough room.
• clear() to reset whole object?

Wont

• PIR class based upon a PCF8574?
  • separate class
• timestamp per PIR
  • lastRead, lastTriggered?
  • taking "a lot of RAM" for every pin
• add statistics?
  • nr of calls - high% - low%
  • duration
• investigate noise (what noise)
• remove(pin)
  • difficult, more admin, expectations...