Suspend state | Cypress Semiconductor
Support & Community
Last Updated: October 02, 2011
The customers board goes into suspend state when it is unplugged from the bus. How to you keep the EZUSB (AN21xx) from going into the suspend state when it is self powered and removed from the bus?
A USB device recognizes a Suspend request as three milliseconds of the bus-idle state. When the EZ-USB detects this condition,it asserts the USB interrupt (INT2) and the Suspend interrupt autovector (vector #3).If the CPU is in reset when a Suspend condition is detected on the bus, the EZ-USB automatically turns off its oscillators (and keep the CPU in reset) until an enabled Wakeup source is asserted.If you wish to inhibit the suspend mode input a logic low on the WAKEUP pin.