4.
Hardware User Guide
4.1
On-Board Debugger Overview
AVR-IoT Wx contains an on-board debugger for programming and debugging. The on-board debugger is a composite
USB device consisting of several interfaces:
• A debugger that can program and debug the ATmega4808 in Atmel Studio/MPLAB X IDE
• A mass storage device that allows drag-and-drop programming of the ATmega4808
• A virtual serial port (CDC) that is connected to a Universal Asynchronous Receiver/Transmitter (UART) on the
ATmega4808, and provides an easy way to communicate with the target application through terminal software
• A Data Gateway Interface (DGI) for code instrumentation with logic analyzer channels (debug GPIO) to visualize
program flow
The on-board debugger controls a Power and Status LED (marked PS) on the AVR-IoT Wx Board. The table below
shows how the LED is controlled in different operation modes.
Table 4-1. On-Board Debugger LED Control
Operation Mode
Power and Status LED
Boot Loader mode
The LED blinks slowly during power-up
Power-up
The LED is ON
Normal operation
The LED is ON
Programming
Activity indicator: The LED blinks slowly during programming/debugging
Drag-and-drop
programming
Success:
The LED blinks slowly for 2 sec.
Failure:
The LED blinks rapidly for 2 sec.
Fault
The LED blinks rapidly if a power Fault is detected
Sleep/Off
The LED is OFF. The on-board debugger is either in a sleep mode or powered down.
This can occur if the board is externally powered.
Info:
Slow blinking is approximately 1 Hz, and rapid blinking is approximately 5 Hz.
4.1.1
Debugger
The on-board debugger on the AVR-IoT Wx Board appears as a Human Interface Device (HID) on the host
computer’s USB subsystem. The debugger supports full-featured programming and debugging of the ATmega4808
using Atmel Studio/MPLAB X IDE, as well as some third-party IDEs.
Remember:
Keep the debugger’s firmware up-to-date. Firmware upgrades are done automatically when
using Atmel Studio/MPLAB X IDE.
4.1.2
Virtual Serial Port (CDC)
The virtual serial port (CDC) is a general purpose serial bridge between a host PC and a target device.
AVR-IoT Wx Hardware User Guide
Hardware User Guide
©
2020 Microchip Technology Inc.
User Guide
DS50002805B-page 9
