Keyboard not working unable to switch back MacOS
I have a 5 year old iMac running the latest MacOS. I run Windows 7 through Boot Camp for the first time from Startup Disk. Now I can’t use Option to select startup disk, it doesn’t display any disk and jump directly to Windows after the sound and few sounds black screen, it seems like I never press anything. Not only this Option key not working but also Command R or Command Option R don’t work either. I tried on other Apple USB keyboard it result the some thing. Once go into Windows system I’m be able to use those keyboards to enter password and other stuff, looks like it only not working during the startup period...
Moreover, I don’t see Macintosh HD under Bootcamp control panel in windows. Even I select restart from OS X in Boot Camp application, still it startup in Windows.
Any ideas what happened there and what to do to recover my MacOS...
iMac Line (2012 and Later)