Figure 3-2. MCU Board Block Diagram
3.1.1.
Power Supply
The ATSAMD21MOTOR MCU card takes 3.3VDC supply from the 67-pin edge connector. Both the
EDBG device and the Main MCU operates from 3.3VDC. The power supply selection jumper on the
Driver board should be connected to 3V3 (silk screen text) selection.
3.1.2.
Main MCU Circuit
The ATSAMD21MOTOR has an ATSAMD21J18A device. The device is intended to work with MCU
internal clock source. A 32.768kHz crystal is connected externally to the MCU.
3.1.3.
Embedded Debugger
The ATSAMD21J18A MCU is interfaced to the EDBG debug device. The EDBG uses SWD interface for
programming and debugging the main MCU. A debug header is also provided on the MCU board with
ARM Cortex
®
debug pinout. An external debugger can be connected to this debug port.
The DGI is a proprietary communication interface used by the Atmel Data Visualizer software to
communicate with the development kits through the EDBG. SERCOM4 of the ATSAMD21J18A
connected to the EDBG device support DGI SPI interface and uses Atmel ADP protocol. The MCU
SERCOM4 is also connected to the UART channel of the EDBG through a pair of "normally open"
jumpers, the J200 and J201. Shorting these jumpers will enable the CDC UART interface for the main
MCU.
High Speed USB port of the EDBG is accessible at the driver board. EDBG USB enumerates as a
composite device supporting debug, DGI SPI, and CDC interfaces.
The USB port of the ATSAMD21J18A is connected to the Micro-USB connecter on the driver board.
3.2.
ATSAMD21BLDC24V-STK Driver Board
The driver board contains half-bridge MOSFET driver circuits for three-phase BLDC, PMSM motor drive
and supports 12-24VDC recommended bus drive voltage. Individual phase current sense, bus voltage
sense, and back-EMF sense circuits supports development of sensor-less motor drive algorithms. Hall
and Encoder sensor interfaces enables the user to develop sensor-based motor control applications. The
Atmel ATSAMD21BLDC24V-STK [USER GUIDE]
Atmel-42681A-SMART-ARM-based-Motor-Control-Kit_User Guide-02/2016
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