MicroMod Environmental Function Board Hookup Guide
Contributors:
bboyho, 
Elias The Sparkiest
bboyho, Elias The Sparkiest 
Hardware Overview
This section goes over the important features on the MicroMod Environmental Function Board. Of course, we recommend checking out the Resources and Going Further for more information on each sensor.
Power
To power the board, you will need to apply power to a SparkFun Main Board. Power applied will connect to the Function Board's VIN pin, which will be regulated down for the rest of the board with the AP2112 3.3V/600mA voltage regulator.
SGP40
The board includes the Sensirion SGP40 sensor IC which measures air quality. The reserved I2C address for the SGP40 is 0x59. For easy reference, the default address for the SGP40 is labeled on the board.
SHTC3
The board includes the Sensirion SHTC3 sensor IC which measures humidity and temperature. The reserved I2C address for the SHTC3 is 0x70. For easy reference, the default address for the SHTC3 is labeled on the board.
Note: A multiplexer/Mux is required to communicate to multiple SHTC3 sensors on a single bus. The SHTC3 uses the same address as the Qwiic Mux (0x70). For advanced users that are using multiple SHTC3's with the Qwiic Mux, you will need to adjust the Qwiic Mux's default address.
STC31
The board includes the Sensirion STC31 sensor IC which measures CO2 concentrations in N2 and CO2 in air. The reserved I2C address for the STC31 is 0x29. For easy reference, the default address for the STC31 is labeled on the board.
EEPROM
The board includes an I2C EEPROM. Unfortunately, this is not available for the user and was meant to hold board specific information.
LED
There is one LED to indicate when there is power available. You can disable the LED with the PWR jumper
Jumpers
Note: If this is your first time working with jumpers, check out the How to Work with Jumper Pads and PCB Traces tutorial for more information.
The following jumpers are included to configure the board.
- PWR - By default, the jumper with the label
PWRis closed. This jumper connects the 3.3V line and LED. Cutting this jumper will disable the LED. - I2C Pull-up Resistors - By default, this three way jumper labeled
I2Cis closed and connects two pull-up resistors to the I2C data lines. If you have many devices on your I2C data lines, then you may consider cutting these two jumpers. - STC31 Address Selection - There are three jumpers available on the board to adjust the STC31's address. By default, the jumpers are open. The alternative addresses for the sensor are 0x2A, 0x2B, and 0x2C. To select the address, you will need to close the jumper by adding a solder blob to one of the solder jumpers.
MicroMod Function Board Pinout
Depending on your window size, you may need to use the horizontal scroll bar at the bottom of the table to view the additional pin functions. Note that the M.2 connector pins on opposing sides are offset from each other as indicated by the bottom pins where it says (Not Connected)*. There is no connection to pins that have a "-" under the primary function.
| AUDIO | UART | GPIO/BUS | I2C | SDIO | SPI0 | Dedicated |
| Function | Bottom Pin |
Top Pin |
Function | ||||||
|---|---|---|---|---|---|---|---|---|---|
| (Not Connected) | 75 | GND | |||||||
| 3.3V | 74 | 73 | G5 / BUS5 | ||||||
| RTC_3V_BATT | 72 | 71 | G6 / BUS6 | ||||||
| SPI_CS1# | SDIO_DATA3 (I/O) | 70 | 69 | G7 / BUS7 | |||||
| SDIO_DATA2 (I/O) | 68 | 67 | G8 | ||||||
| SDIO_DATA1 (I/O) | 66 | 65 | G9 | ADC_D- | CAM_HSYNC | ||||
| SPI_CIPO1 | SDIO_DATA0 (I/O) | 64 | 63 | G10 | ADC_D+ | CAM_VSYNC | |||
| SPI COPI1 | SDIO_CMD (I/O) | 62 | 61 | SPI_CIPO (I) | |||||
| SPI SCK1 | SDIO_SCK (O) | 60 | 59 | SPI_COPI (O) | LED_DAT | ||||
| AUD_MCLK (O) | 58 | 57 | SPI_SCK (O) | LED_CLK | |||||
| CAM_MCLK | PCM_OUT | I2S_OUT | AUD_OUT | 56 | 55 | SPI_CS# | |||
| CAM_PCLK | PCM_IN | I2S_IN | AUD_IN | 54 | 53 | I2C_SCL1 (I/O) | |||
| PDM_DATA | PCM_SYNC | I2S_WS | AUD_LRCLK | 52 | 51 | I2C_SDA1 (I/O) | |||
| PDM_CLK | PCM_CLK | I2S_SCK | AUD_BCLK | 50 | 49 | BATT_VIN / 3 (I - ADC) (0 to 3.3V) | |||
| G4 / BUS4 | 48 | 47 | PWM1 | ||||||
| G3 / BUS3 | 46 | 45 | GND | ||||||
| G2 / BUS2 | 44 | 43 | CAN_TX | ||||||
| G1 / BUS1 | 42 | 41 | CAN_RX | ||||||
| G0 / BUS0 | 40 | 39 | GND | ||||||
| A1 | 38 | 37 | USBHOST_D- | ||||||
| GND | 36 | 35 | USBHOST_D+ | ||||||
| A0 | 34 | 33 | GND | ||||||
| PWM0 | 32 | 31 | Module Key | ||||||
| Module Key | 30 | 29 | Module Key | ||||||
| Module Key | 28 | 27 | Module Key | ||||||
| Module Key | 26 | 25 | Module Key | ||||||
| Module Key | 24 | 23 | SWDIO | ||||||
| UART_TX2 (O) | 22 | 21 | SWDCK | ||||||
| UART_RX2 (I) | 20 | 19 | UART_RX1 (I) | ||||||
| CAM_TRIG | D1 | 18 | 17 | UART_TX1 (0) | |||||
| I2C_INT# | 16 | 15 | UART_CTS1 (I) | ||||||
| I2C_SCL (I/0) | 14 | 13 | UART_RTS1 (O) | ||||||
| I2C_SDA (I/0) | 12 | 11 | BOOT (I - Open Drain) | ||||||
| D0 | 10 | 9 | USB_VIN | ||||||
| SWO | G11 | 8 | 7 | GND | |||||
| RESET# (I - Open Drain) | 6 | 5 | USB_D- | ||||||
| 3.3V_EN | 4 | 3 | USB_D+ | ||||||
| 3.3V | 2 | 1 | GND | ||||||
| Alternative Function | Primary Function | Bottom Pin |
Top Pin |
Primary Function | Alternative Function |
|---|---|---|---|---|---|
| (Not Connected) | 75 | GND | |||
| VIN | 74 | 73 | 3.3V | ||
| VIN | 72 | 71 | Power EN | ||
| - | 70 | 69 | - | ||
| - | 66 | 65 | - | ||
| - | 64 | 63 | - | ||
| - | 62 | 61 | - | ||
| - | 60 | 59 | - | ||
| - | 58 | 57 | - | ||
| - | 56 | 55 | - | ||
| - | 54 | 53 | - | ||
| - | 52 | 51 | - | ||
| - | 50 | 49 | - | ||
| - | 48 | 47 | - | ||
| - | 46 | 45 | GND | ||
| - | 44 | 43 | - | ||
| - | 42 | 41 | - | ||
| - | 40 | 39 | GND | ||
| - | 38 | 37 | - | ||
| EEPROM_A0 | 36 | 35 | - | ||
| EEPROM_A1 | 34 | 33 | GND | ||
| EEPROM_A2 | 32 | 31 | Module Key | ||
| Module Key | 30 | 29 | Module Key | ||
| Module Key | 28 | 27 | Module Key | ||
| Module Key | 26 | 25 | Module Key | ||
| Module Key | 24 | 23 | - | ||
| - | 22 | 21 | I2C_SCL | ||
| - | 20 | 19 | I2C_SDA | ||
| - | 18 | 17 | - | ||
| - | 16 | 15 | - | ||
| - | 14 | 13 | - | ||
| - | 12 | 11 | - | ||
| - | 10 | 9 | - | ||
| - | 8 | 7 | - | ||
| - | 6 | 5 | - | ||
| - | 4 | 3 | - | ||
| - | 2 | 1 | GND |
| Signal Group | Signal | I/O | Description | Voltage | Power | 3.3V | I | 3.3V Source | 3.3V |
|---|---|---|---|---|
| GND | Return current path | 0V | ||
| USB_VIN | I | USB VIN compliant to USB 2.0 specification. Connect to pins on processor board that require 5V for USB functionality | 4.8-5.2V | |
| RTC_3V_BATT | I | 3V provided by external coin cell or mini battery. Max draw=100μA. Connect to pins maintaining an RTC during power loss. Can be left NC. | 3V | |
| 3.3V_EN | O | Controls the carrier board's main voltage regulator. Voltage above 1V will enable 3.3V power path. | 3.3V | |
| BATT_VIN/3 | I | Carrier board raw voltage over 3. 1/3 resistor divider is implemented on carrier board. Amplify the analog signal as needed for full 0-3.3V range | 3.3V | |
| Reset | Reset | I | Input to processor. Open drain with pullup on processor board. Pulling low resets processor. | 3.3V |
| Boot | I | Input to processor. Open drain with pullup on processor board. Pulling low puts processor into special boot mode. Can be left NC. | 3.3V | |
| USB | USB_D± | I/O | USB Data ±. Differential serial data interface compliant to USB 2.0 specification. If UART is required for programming, USB± must be routed to a USB-to-serial conversion IC on the processor board. | |
| USB Host | USBHOST_D± | I/O | For processors that support USB Host Mode. USB Data±. Differential serial data interface compliant to USB 2.0 specification. Can be left NC. | |
| CAN | CAN_RX | I | CAN Bus receive data. | 3.3V |
| CAN_TX | O | CAN Bus transmit data. | 3.3V | |
| UART | UART_RX1 | I | UART receive data. | 3.3V |
| UART_TX1 | O | UART transmit data. | 3.3V | |
| UART_RTS1 | O | UART ready to send. | 3.3V | |
| UART_CTS1 | I | UART clear to send. | 3.3V | |
| UART_RX2 | I | 2nd UART receive data. | 3.3V | |
| UART_TX2 | O | 2nd UART transmit data. | 3.3V | |
| I2C | I2C_SCL | I/O | I2C clock. Open drain with pullup on carrier board. | 3.3V |
| I2C_SDA | I/O | I2C data. Open drain with pullup on carrier board | 3.3V | |
| I2C_INT# | I | Interrupt notification from carrier board to processor. Open drain with pullup on carrier board. Active LOW | 3.3V | |
| I2C_SCL1 | I/O | 2nd I2C clock. Open drain with pullup on carrier board. | 3.3V | |
| I2C_SDA1 | I/O | 2nd I2C data. Open drain with pullup on carrier board. | 3.3V | |
| SPI | SPI_COPI | O | SPI Controller Output/Peripheral Input. | 3.3V |
| SPI_CIPO | I | SPI Controller Input/Peripheral Output. | 3.3V | |
| SPI_SCK | O | SPI Clock. | 3.3V | |
| SPI_CS# | O | SPI Chip Select. Active LOW. Can be routed to GPIO if hardware CS is unused. | 3.3V | |
| SPI/SDIO | SPI_SCK1/SDIO_CLK | O | 2nd SPI Clock. Secondary use is SDIO Clock. | 3.3V |
| SPI_COPI1/SDIO_CMD | I/O | 2nd SPI Controller Output/Peripheral Input. Secondary use is SDIO command interface. | 3.3V | |
| SPI_CIPO1/SDIO_DATA0 | I/O | 2nd SPI Peripheral Input/Controller Output. Secondary use is SDIO data exchange bit 0. | 3.3V | |
| SDIO_DATA1 | I/O | SDIO data exchange bit 1. | 3.3V | |
| SDIO_DATA2 | I/O | SDIO data exchange bit 2. | 3.3V | |
| SPI_CS1/SDIO_DATA3 | I/O | 2nd SPI Chip Select. Secondary use is SDIO data exchange bit 3. | 3.3V | |
| Audio | AUD_MCLK | O | Audio master clock. | 3.3V |
| AUD_OUT/PCM_OUT/I2S_OUT/CAM_MCLK | O | Audio data output. PCM synchronous data output. I2S serial data out. Camera master clock. | 3.3V | |
| AUD_IN/PCM_IN/I2S_IN/CAM_PCLK | I | Audio data input. PCM syncrhonous data input. I2S serial data in. Camera periphperal clock. | 3.3V | |
| AUD_LRCLK/PCM_SYNC/I2S_WS/PDM_DATA | I/O | Audio left/right clock. PCM syncrhonous data SYNC. I2S word select. PDM data. | 3.3V | |
| AUD_BCLK/PCM_CLK/I2S_CLK/PDM_CLK | O | Audio bit clock. PCM clock. I2S continuous serial clock. PDM clock. | 3.3V | |
| SWD | SWDIO | I/O | Serial Wire Debug I/O. Connect if processor board supports SWD. Can be left NC. | 3.3V |
| SWDCK | I | Serial Wire Debug clock. Connect if processor board supports SWD. Can be left NC. | 3.3V | |
| ADC | A0 | I | Analog to digital converter 0. Amplify the analog signal as needed to enable full 0-3.3V range. | 3.3V |
| A1 | I | Analog to digital converter 1. Amplify the analog signal as needed to enable full 0-3.3V range. | 3.3V | |
| PWM | PWM0 | O | Pulse width modulated output 0. | 3.3V |
| PWM1 | O | Pulse width modulated output 1. | 3.3V | |
| Digital | D0 | I/O | General digital input/output pin. | 3.3V |
| D1/CAM_TRIG | I/O | General digital input/output pin. Camera trigger. | 3.3V | |
| General/Bus | G0/BUS0 | I/O | General purpose pins. Any unused processor pins should be assigned to Gx with ADC + PWM capable pins given priority (0, 1, 2, etc.) positions. The intent is to guarantee PWM, ADC and Digital Pin functionality on respective ADC/PWM/Digital pins. Gx pins do not guarantee ADC/PWM function. Alternative use is pins can support a fast read/write 8-bit or 4-bit wide bus. | 3.3V |
| G1/BUS1 | I/O | 3.3V | ||
| G2/BUS2 | I/O | 3.3V | ||
| G3/BUS3 | I/O | 3.3V | ||
| G4/BUS4 | I/O | 3.3V | ||
| G5/BUS5 | I/O | 3.3V | ||
| G6/BUS6 | I/O | 3.3V | ||
| G7/BUS7 | I/O | 3.3V | ||
| G8 | I/O | General purpose pin | 3.3V | |
| G9/ADC_D-/CAM_HSYNC | I/O | Differential ADC input if available. Camera horizontal sync. | 3.3V | |
| G10/ADC_D+/CAM_VSYNC | I/O | Differential ADC input if available. Camera vertical sync. | 3.3V | |
| G11/SWO | I/O | General purpose pin. Serial Wire Output | 3.3V |
Board Dimensions
The board uses the standard MicroMod Function Board size which measures about 1.50"x2.56".
