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 1. 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.