Info:
The commands listed here are triggered by the content being sent to the mass storage emulated
disk, and no feedback is provided in the case of either success or failure.
3.1.4
Data Gateway Interface (DGI)
Data Gateway Interface (DGI) is a USB interface for transporting raw and timestamped data between on-board
debuggers and host computer-based visualization tools.
is used on the host computer to
display debug GPIO data. It is available as a plug-in for MPLAB
®
X IDE or a stand-alone application that can be used
in parallel with Atmel Studio/Microchip MPLAB
®
X IDE.
Although DGI encompasses several physical data interfaces, the ATtiny3217 Curiosity Nano implementation includes
logic analyzer channels:
• Two debug GPIO channels (also known as DGI GPIO)
3.1.4.1
Debug GPIO
Debug GPIO channels are timestamped digital signal lines connecting the target application to a host computer
visualization application. They are typically used to plot the occurrence of low-frequency events on a time-axis – for
example, when certain application state transitions occur.
The figure below shows the monitoring of the digital state of a mechanical switch connected to a debug GPIO in
MPLAB Data Visualizer.
Figure 3-2. 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.
3.1.4.2
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.
ATtiny3217
Curiosity Nano
©
2020 Microchip Technology Inc.
User Guide
DS40002193A-page 12
