Utilizing VBUS ISR on CY8CKIT-030 | Cypress Semiconductor
Utilizing VBUS ISR on CY8CKIT-030
I'm developing a PSoC3 device on the CY8CKIT-030 development board. I plan on using the USBUART component to communicate with it serially when plugged into a computer. It will be a self-powered device, so it may be plugged into the host computer while already running. I would like to have an interrupt service routine run when a rising edge is detected on the VBUS/VCC pin of the mini USB port (connected to a pulled-down digital input pin), which will then start the USBUART component, enumerate on the host, and transfer my data.
The issue I'm having is that according to the development board user guide, the USB connector's VCC pin is tied to both the 9V battery input and the 12V AC adaptor input. The schematic shows VBUS connected to Pin 9 on the PSoC3, and when I use a voltage probe on that pin, it reads 5V if my adaptor is plugged in.
How can I develop and test a VBUS-based ISR on this development board when all the power inputs are tied together?
Thanks in advance for your help.