On-Board Debugger Connections - Microchip Technology AVR-IoT Wx Hardware User's Manual

Figure 4-2. Monitoring Debug GPIO with MPLAB Data Visualizer
Debug GPIO channels are timestamped, so the resolution of DGI GPIO events is determined by the resolution of the
DGI timestamp module.
Important: Although bursts of higher-frequency signals can be captured, the useful frequency range of
signals for which debug GPIO can be used is up to about 2 kHz. Attempting to capture signals above this
frequency will result in data saturation and overflow, which may cause the DGI session to be aborted.
4.1.4.2 Timestamping
DGI sources are timestamped as they are captured by the debugger. The timestamp counter implemented in the
Curiosity Nano debugger increments at 2 MHz frequency, providing a timestamp resolution of a half microsecond.
4.2

On-Board Debugger Connections

The table below shows the connections between the target and the debugger section. All connections between the
target and the debugger are tri-stated as long as the debugger is not actively using the interface. Hence, since there
are little contaminations of the signals, the pins can be configured to anything the user wants.
For further information on how to use the capabilities of the on-board debugger, see
Overview.
Table 4-3. On-Board Debugger Connections
ATmega4808 Pin Debugger Pin
PF1
PF0
UPDI
PF6
PF5
©
2020 Microchip Technology Inc.
Function
CDC TX UART2 RX (ATmega4808 RX line)
CDC RX UART2 TX (ATmega4808 TX line)
DBG0 UPDI
DBG1 DGI GPIO0
DBG2 DGI GPIO1
AVR-IoT Wx Hardware User Guide
User Guide
Hardware User Guide
4.1 On-Board Debugger
Shared Functionality
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SW0
SW1
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