Curiosity Nano; On-Board Debugger - Microchip Technology SAM E51 Curiosity Nano User Manual

3.

Curiosity Nano

The Curiosity Nano is an evaluation platform that provides a set of small boards with access to most of the
microcontroller's I/O. The platform consists of a series of low pin-count microcontroller (MCU) boards, which are
integrated with MPLAB X IDE to present relevant user guides, application notes, data sheets, and example code. The
platform features a virtual COM port (CDC) for serial communication to a host PC, and a Data Gateway Interface
(DGI) GPIO.
3.1

On-Board Debugger

The SAME51J20A Curiosity Nano contains an on-board debugger for programming and debugging. The on-board
debugger is a composite USB device of several interfaces: a debugger, a mass storage device, a data gateway, and
a virtual COM port (CDC). Together with MPLAB X IDE, the on-board debugger interface can program and debug the
SAME51J20A. A Data Gateway Interface (DGI) is available for use with logic analyzer channels for code
instrumentation, and to visualize program flow. DGI GPIOs can be graphed using the Data Visualizer. The Virtual
COM port is connected to a UART on the SAME51J20A and provides an easy way to communicate with the target
application through terminal software. The on-board debugger controls one Power/Status LED (marked PS) on the
SAME51J20A Curiosity Nano board. The following table shows how the LED is controlled in different operation
modes.
Table 3-1. On-Board Debugger LED Control
Operation Mode
Boot Loader mode LED blink at 1 Hz during power up.
Power-up
Normal operation
Programming
Fault
Sleep/Off
3.1.1 Virtual COM Port
A general-purpose USB serial bridge between a host PC and a target device.
3.1.1.1 Overview
The debugger implements a composite USB device that includes a standard Communications Device Class (CDC)
interface, which appears on the host as a virtual COM Port. The CDC can be used to stream arbitrary data in both
directions between the host and the target. Characters sent from the host will appear in UART form on the CDC TX
pin, and UART characters sent into the CDC RX pin will be sent back to the host. On Windows machines, the CDC
will enumerate as the Curiosity Virtual COM Port and appear in the Ports section of the device manager. The COM
port number is usually shown here.
Tip: On older Windows systems a USB driver is required for the CDC. This driver is included in MPLAB X
IDE installations. On Linux machines, the CDC will enumerate and appear as /dev/ttyACM#. On MAC
machines, the CDC will enumerate and appear as /dev/tty.usbmodem#. Depending on which terminal
program is used, it will appear in the available list of modems as usbmodem#.
3.1.1.2 Limitations
Not all UART features are implemented in the debugger CDC. The constraints are outlined here:
• Baud rate: Must be in the range of 1200 bps to 500 kbps. Values outside this range will be capped to these
values without warning. Baud rate can be changed on-the-fly.
©
2020 Microchip Technology Inc.
Status LED
LED is lit - constant.
LED is lit - constant.
Activity indicator; the LED flashes slowly during programming or debugging.
The LED flashes fast if a power fault is detected.
LED is Off. The on-board debugger is either in Sleep mode or powered down. This can occur if
the kit is externally powered.
User Guide
EV76S68A
Curiosity Nano
DS70005432A-page 5