1. Power supply
The BMAN5542DSA is generally bus-powered, typically 24V DC. If it is not connected to the bus, you may supply power (up to 42V DC) for operating and evaluating it. There is a rectifier on the BMAN5542DSA so that either pin can connect to the positive or negative terminal of the power.

2. Calibration mode
A smoke detector usually needs to be calibrated according to the operating environment. The way to enter the calibration mode is to short the PA0 and GND (the BD connection holes on the board) before power-on. After entering the calibration mode, the red LED light flashes once per second, lasts for 4 seconds. If the calibration is successful, the board enters the normal mode. If the calibration is unsuccessful, the red LED will be on.

3. Normal mode
In this mode, the board works normally, and the red LED flashes once every 40 seconds.

4. Alarm mode
When the smoke is detected, the alarm mode is entered and the red LED continues flashing.

5. Fault Detection
When the board self detects a fault, the red LED flashes twice every 40 seconds.

This board has no built-in protocol for communication with the control panel. You must carry out secondary development by yourself. After development, you may use e-Link to perform ICP (in-circuit-programming) via the 4-pin PG connection holes on the board. Please refer to the schematics for the pin positions.

1. MCU : Holtek BA45F5542, Smoke Detector Flash MCU with Power Line Transceiver, including datasheet,
   package dimension, etc.
2. Application Note: AN0534EN, BA45F55xx with Power Line Transceiver Application Note