Arduino MKR Zero
Overview
The Arduino MKR Zero built with smaller MKR form factor and powered by Atmel’s SAMD21 MCU. This board come with microSD card holder that allows you to play with music files with no extra hardware.
Hardware
ATSAMD21G18A ARM Cortex-M0+ processor at 48 MHz
32.768 kHz crystal oscillator
256 KiB flash memory and 32 KiB of RAM
One user LEDs
One reset button
microSD card slot
ATECC508A secure element
Supported Features
The arduino_mkrzero board supports the hardware features listed below.
- on-chip / on-board
- Feature integrated in the SoC / present on the board.
- 2 / 2
-
Number of instances that are enabled / disabled.
Click on the label to see the first instance of this feature in the board/SoC DTS files. -
vnd,foo -
Compatible string for the Devicetree binding matching the feature.
Click on the link to view the binding documentation.
Type |
Location |
Description |
Compatible |
|---|---|---|---|
CPU |
on-chip |
ARM Cortex-M0+ CPU1 |
|
ADC |
on-chip |
Atmel SAM0 family ADC1 |
|
ARM architecture |
on-chip |
Atmel SAM0 multi-protocol (UART, SPI, I2C) SERCOM unit2 |
|
on-chip |
For locating the Device ID (serial number) on Atmel SAM0 devices1 |
||
Clock control |
on-chip |
Atmel SAM0 Main Clock Controller (MCLK)1 |
|
on-chip |
Atmel SAMD0 Generic Clock Controller (GCLK)1 |
||
Counter |
on-chip |
Atmel SAM0 basic timer counter (TC) operating in 32-bit wide mode2 |
|
DAC |
on-chip |
Atmel SAM0 family DAC1 |
|
DMA |
on-chip |
Atmel SAM0 DMA controller1 |
|
Flash controller |
on-chip |
Atmel SAM0 NVMC (Non-Volatile Memory Controller)1 |
|
GPIO & Headers |
on-chip |
SAM0 GPIO PORT node2 |
|
on-board |
GPIO pins exposed on Arduino MKR headers1 |
||
I2C |
on-chip |
Atmel SAM0 series SERCOM I2C1 |
|
Interrupt controller |
on-chip |
ARMv6-M NVIC (Nested Vectored Interrupt Controller) controller1 |
|
on-chip |
Atmel SAM0 series External Interrupt Controller1 |
||
LED |
on-board |
Group of GPIO-controlled LEDs1 |
|
MTD |
on-chip |
Flash node1 |
|
on-board |
Fixed partitions of a flash (or other non-volatile storage) memory1 |
||
Pin control |
on-chip |
Atmel SAM0 PINMUX2 |
|
on-chip |
Atmel SAM0 Pinctrl Container1 |
||
RTC |
on-chip |
Atmel SAM0 RTC1 |
|
Serial controller |
on-chip |
Atmel SAM0 SERCOM UART driver1 |
|
SPI |
on-chip |
Atmel SAM0 SERCOM SPI controller2 |
|
SRAM |
on-chip |
Generic on-chip SRAM description1 |
|
Timer |
on-chip |
ARMv6-M System Tick1 |
|
USB |
on-chip |
Atmel SAM0 USB in device mode1 |
|
Watchdog |
on-chip |
Atmel SAM0 watchdog1 |
Connections and IOs
The Arduino store [1] has detailed information about board connections. Download the Arduino MKR Zero Schematic [2] for more detail.
System Clock
The SAMD21 MCU is configured to use the 32.768 kHz external oscillator with the on-chip PLL generating the 48 MHz system clock. The internal APB and GCLK unit are set up in the same way as the upstream Arduino libraries.
Serial Port
The SAMD21 MCU has 6 SERCOM based USARTs. SERCOM5 is available on pins 13(PA23) and 14(PA22).
PWM
The SAMD21 MCU has 3 TCC based PWM units with up to 4 outputs each and a period of 24 bits or 16 bits.
SPI Port
The SAMD21 MCU has 6 SERCOM based SPIs. On the Arduino MKR Zero, SERCOM1 is available on pin 8, 9, and 10. SERCOM2 connect to microSD card slot as SPI interface.
I2C Port
The SAMD21 MCU has 6 SERCOM based I2Cs. SERCOM0 is available on pin 11(PA08) and 12(PA09). This I2C bus also available as ESLOV(JST SH 5pin) socket. ATECC508A secure element is connect to this I2C bus.
USB Device Port
The SAMD21 MCU has a USB device port that can be used to communicate with a host PC. See the USB device support sample applications for more, such as the USB CDC-ACM sample which sets up a virtual serial port that echos characters back to the host PC.
DAC
The SAMD21 MCU has a single channel DAC with 10 bits of resolution. On the Arduino MKR Zero, the DAC is available on pin A0.
Programming and Debugging
The Arduino MKR Zero ships the BOSSA compatible bootloader. The bootloader can be entered by quickly tapping the reset button twice.
Flashing
Build the Zephyr kernel and the Hello World sample application:
west build -b arduino_mkrzero samples/hello_world
Connect the MKR Zero to your host computer using USB
Connect a 3.3 V USB to serial adapter to the board and to the host. See the Serial Port section above for the board’s pin connections.
Run your favorite terminal program to listen for output. Under Linux the terminal should be
/dev/ttyACM0. For example:$ minicom -D /dev/ttyACM0 -o
The -o option tells minicom not to send the modem initialization string. Connection should be configured as follows:
Speed: 115200
Data: 8 bits
Parity: None
Stop bits: 1
Tap the reset button twice quickly to enter bootloader mode
Flash the image:
west build -b arduino_mkrzero samples/hello_world west flash
You should see “Hello World! arduino_mkrzero” in your terminal.