Microchip Technology MCP2221 - Page 33

Testing Board Features
 2016 Microchip Technology Inc. DS50002480A-page 33
3.3.7.1 TAB OPERATION
To control the digital I/O pins, follow these steps:
1. Select the GPIO Expander tab.
2. Configure the pin directions (input or output) under the “Set GPIO Direction”
section. The configuration only becomes active after the user clicks the Submit
Pin Directions button.
3. For the pins that are set as outputs, the “Configure Pin State (if Output)” section
allows the user to change their state in one of the following ways:
- All at once, if the “Instant Command” check box is cleared and when
clicking the Submit Pin States button;
or
- Individually (real-time state toggling), the “Instant Command” check box is
selected.
In case a pin is configured as an input, these pin state control commands are ignored.
Reading the states for all eight general purpose pins can be done by either:
• Automatically (continuously, every 100 milliseconds), in case the “Auto Read
Every 100ms” check box is selected;
or
• Manually, by clicking on the Read Pin States button.
Figure 3-11 shows an example of using the GPIO Expander tab.
FIGURE 3-11: INTERFACING THE GPIO EXPANDER