PrettyPins PDF on GitHub.

Power

There are two ways to power the Metro M7 1011:

• USB-C port- This is used for both powering and programming the board. You can power it with any USB C cable.
• DC Jack - The DC Jack is a 5.5mm/2.1mm center-positive DC connector, which is the most common available. Provide about 6V-12V here to power the Metro M7 1011.

There is a switch to control power from the DC jack:

• DC Jack On/Off Switch - This switch can turn incoming power from the DC jack on or off. It only controls the DC jack, it has no affect on the USB port.

The following pins are related to power on the Metro M7 1011:

• 3.3V - this is the output from the 3.3V regulator, it can supply 500mA peak.
• 5V - this is the output from the 5V regulator (when DC jack is used), or from USB. It can supply ~500mA peak from USB and ~800mA peak from DC.
• GND - this is the common ground for all power and logic.
• VIN - this is the higher of the DC jack or USB voltage. So if the DC jack is plugged in and 9V, Vin is 9V. If only USB connected, this will be 5V.

There is an LED to indicate when the board is powered:

• Power LED - Above the USB-C port, on the front of the board, is the power LED, labeled ON. It is the green LED.

i.MX RT1011 Processor and QSPI Flash

The Metro M7 is powered by the NXP i.MX RT1011 processor. This is an ARM Cortex M7 processor running at 500 MHz. It has 128KB of SRAM in-chip, along with high speed USB.

Next to the processor is the 8MB QSPI flash. It is connected to pins not broken out on the Metro, so you can use SPI without issues. The flash memory is shared between the CircuitPython program the Metro is running and any file storage used by CircuitPython itself. This means when using CircuitPython, you have around 6MB of memory available for code, images, fonts, files, etc.

microSD Card

The Metro M7 comes with a microSD card slot. This enables you to store audio files, fonts, images, etc. on a microSD card, providing significantly more space than the flash memory alone.

It is wired up for SPI interfacing. To access the SD card, use the following pins:

• SCK - This is the SPI clock pin.
• MOSI - This is the SPI Microcontroller Out / Sensor In pin.
• MISO - This is the SPI Microcontroller In / Sensor Out pin.
• SD_CS - This is the SD chip select pin.
• SD_CD - This is the SD chip detect pin.

Logic Pins

These are the general purpose I/O pin set for the microcontroller.

Top Row:

• D0 / RX - GPIO D0, also receive (input) pin/RX for UART.
• D1 / TX - GPIO D1, also transmit (output) pin/TX for UART
  
• D2 through D12 - These are general purpose GPIO
• D13 - GPIO D13 and is connected to the red LED marked D13 next to the reset button.
• SDA - the I2C data pin. There's a 10K pull up on this pin to 3V already installed
• SCL - the I2C clock pin. There's a 10K pull up on this pin to 3V already installed

Bottom Row:

• A0 - This pin is analog output A0. You can set the raw voltage to anything from 0 to 3.3V. Unlike PWM outputs this is a true analog output.
• A1 thru A5 - These are analog inputs as well as digital I/O pins.

Right side:

• SCK/MOSI/MISO - These are the hardware SPI pins, are are connected to the 2x3 header on the right hand side.

NeoPixel and Red LED

• NeoPixel LED - This addressable RGB NeoPixel LED, labeled NEO on the board, works both as a status LED (in CircuitPython and the bootloader), and can be controlled with code. It is available in CircuitPython as board.NEOPIXEL.
• D13 LED - This little red LED, labeled D13 on the board, is on or blinks during certain operations (such as pulsing when in the bootloader), and is controllable in code. It is available in CircuitPython as board.LED.

STEMMA QT

This JST SH 4-pin STEMMA QT connector breaks out I2C (SCL, SDA, 3.3V, GND). It allows you to connect to various breakouts and sensors with STEMMA QT connectors or to other things using assorted associated accessories. It works great with any STEMMA QT or Qwiic sensor/device. You can also use it with Grove I2C devices thanks to this handy cable.

In CircuitPython, this port can be accessed with board.STEMMA_I2C().

Reset Button and RST Pins

• Reset button - The reset button restarts the board and helps enter the bootloader. You can click it once to reset the board without unplugging the USB cable or battery. Alternatively, tap once, and then tap again while the NeoPixel status LED is purple to enter the UF2 bootloader (needed to load CircuitPython).
• The RST pin can be used to reset the board. Tie to ground manually to reset the board.

Boot Mode Switches

The boot mode switches (labeled BOOT SEL on the board silk) are used to get into the ROM bootloader. The switch has two individual switches: B0 and B1. The photo shows both switches in the OFF position, but for normal operation B0 should be OFF and B1 should be ON.

The individual switches are set to ON (or 1) when they are moved next to the ON text on the switch housing and OFF (or 0) when they are moved next to their labels on the board silk. You can find more information on entering the bootloader with these switches on the Installing the Bootloader page in this guide.

Debug Interface

If you'd like to do more advanced development, trace-debugging, or not use the bootloader, we have the SWD interface exposed. You can use any 2x5 0.05" pitch SWD interface to connect. We suggest a J-Link.

Alternatively, you can use the following version. You'll need an adapter and cable to convert the 2x10 JTAG cable to SWD.