I will check internally and provide you.
Please find the attached document and firmware.
>> In this project I am sending a vendor command-0x88, to imitate a button press. Hence, I have added this vendor interface.
>> In addition to vendor command, I have configured GPIO 45 as an input pin and register for a callback function in CyU3PGpioInit() API. In SuperSpeed explorer kit GPIO 45 is provided as Switch (SW2). If you press this switch, it will trigger an interrupt callback.
>> If you use e-cam view application for video streaming, ‘Enter’ key can be pressed to initiate Still Capture.
The captured still image is saved as a .bmp file in the Still Capture path which can be provided in the e-CamView Application.
So you can get the screen shots in the three ways (1. vendor command, 2. Press GPIO 45 in explorer kit come under hardware trigger, the other comes under software trigger) mentioned above with the attached firmware.
Thank you very much!