The Integrated Sensor board provides a new level of integration to microcontroller development systems. Instead of simply breaking out the processor's pins, the board integrates a wide variety of sensors and memory directly onto the board itself, providing an extremely compact platform.

To reduce cost, only the desired features are populated at manufacture. In fact, the cost savings of using a single PCB for every sub-system even allows this design to be cost competitive with mass-manufactured breakout boards.

This design is fully compatible with the Arduino IDE, no modifications required.

FEATURES

All boards have:

• USB programming
• USB type C, or micro USB
• ATmega328p microcontroller, 5V, 16MHz
• Custom LED colors on serial, and GPIO 13
• 6 GPIO pins for expansion (plus 5V and GND)
• 5V processor running at 16MHz

Optional Features:

• 16MB SPI flash
• accelerometer
• barometer
• microSD socket
• phototransistor
• temperature sensor
• ws2812 RGB Led

DETAILS

• USB programming

(STANDARD ON ALL BOARDS)

Programming is done over the USB port, either USB-C or micro USB depending on your selection. USB to serial conversion is accomplished with the CP2104, which can achieve a baud rate of up to 2 mbits. Typically, no additional driver is required for this chip.

• ATmega328p microcontroller

(STANDARD ON ALL BOARDS)

The ATmega328p processor runs at 5V, and is clocked at 16MHz by an external crystal. The board comes flashed with the Arduino Pro/Pro Mini bootloader for ease of use.

• 16MB SPI flash

(OPTIONAL)

The flash chip used is the W25Q128, a 16MB (128Mbit) flash chip from winbond. This is an excellent choice if you have a moderately large number of sensor readings to store, but don't need the capacity of a microSD card. Code overhead and power consumption are both lower for this chip than for a memory card. 16MB might be small compared to a microSD card, but for many applications, it is sufficient. If you store 3 16-bit readings per second, it would take you over a month to fill up. The flash chip select pin is A1 (PC1)

• Accelerometer

(OPTIONAL)

The accelerometer used is the MMA8452Q, a 3 axis chip which communicates over I2C. It's sensitivity can be set from software to either +-2G, +-4G, or +-8G. This chip uses only the hardware I2C lines (pins A4 and A5).

• Barometer

(OPTIONAL)

The Barometer used is the HP203b, from HopeRF. It can directly measure both the temperature and pressure of the surrounding air, and based on these values, also internally calculates altitude. This altitude reading has a resolution of down to 0.1m, although testing indicates that noise in the readings limits this to around 2 meters. This Chip uses only the hardware I2C lines (pins A4 and A5).

• microSD socket

(OPTIONAL)

This is just a standard microSD card socket, connected over the SPI port. Great for storing very large amounts of data, and easily reading that data off the board; just unplug the card, and read it from a computer. The chip select line for the microSD card is pin A1 (PC1).

• phototransistor

(OPTIONAL)

This is a visible light phototransistor (Everlight ALS-PT19-315C), designed for measuring ambient light. it's wired into a voltage divider, so getting the value is as simple as reading the voltage on pin A2 (PC2).

• temperature sensor

(OPTIONAL)

The temperature sensor is an active Thermistor from Microchip (MCP9700AT), which outputs an analogue voltage depending on the temperature. The chip features internal calibration, producing an output voltage of 10mV/°C. Getting this voltage is as simple as reading the voltage on pin A3 (PC3).

• ws2812 LED

(OPTIONAL)

This is a serial WS2812B RGB led, connected to pin D10 (PB2).

• GPIO

(OPTIONAL)

There are 6 GPIO pins, along with 5V and ground, brought out to pads along the top of the board. They are pins D2 through D7 (PD2 through PD7).

DIMENSIONS

The PCB measures 1.1" by 1.9" (28mm x 48mm), and mounting holes are sized for M2 screws, and set in 0.1" (2.54mm) from the sides.

DATASHEETS / LIST OF RECOMMENDED LIBRARIES

For more information, including datasheets for each of the components, schematics, and a list of tested, recommended libraries, check out this project's github page