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IOT123 - I2C Max9812 Brick

The IOT123 BRICKS are DIY modular units that can be mashed up with other IOT123 BRICKS, to add functionality to a node or wearable. They are based on the inch square, double-sided protoboards with interconnected through holes.
A number of these BRICKS are expected to be on multiple nodes (Master MCUs - ESP8266 or ATTINY84) on a site. The MCU needs no prior knowledge of the sensors purpose or software needs. It scans for I2C nodes then requests a property dump (sensor data) from each slave. These BRICKs supply 5.0V, 3.3V and another AUX line which is customizable.
This I2C MAX9812 BRICK dumps 3 sound sensing properties:
audMin (0-1023) - lowest value inside the 50ms (20Hz) sample windowaudMax (0-1023) - highest value inside the 50ms (20Hz) sample window audDiff (0-50) - a value derived from the difference of aMin and aMax
Sound Levels using I2C are not expected to be used for continuous readings. Think machine noise levels, meeting/venue room occupancy or sound due to movement (water/friction).
The Keyes type sensor bricks will be abstracted first as they come with vitamins (extra components needed) included and are relatively cheep (I bought 37 for 10AUD). Other boards/circuits will be introduced to the I2C BRICKS.
The through-holes adjacent to the ATTINY85 have been left unused, to enable a pogo pin programmer while the DIP8 is soldered to the PCB.
A further abstraction, packaging the BRICKS in small cylinders that plug into a D1M WIFI BLOCK hub, pumping the values to a MQTT server, is being developed.”

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