----- Original Message ----- > On Sun, Oct 2, 2011 at 7:44 PM, Avi Kivity <a...@redhat.com> wrote: > >> > > >> > A real device also ignores inputs during reset (or if it > >> > doesn't, > >> > we can just emulate that). > >> > >> Maybe this could work: > >> 1 - issue start of reset cycle (raise qemu_irq, unrealize): > >> internal > >> states reset, no I/O. > >> 2 - issue start of I/O, reset held (new phase): evaluate inputs > >> and > >> post outputs, but consider also that reset is still active, so > >> transition is not complete for all devices > > > > This doesn't correspond to real hardware. Each device detects the > > reset edge independently. There is no signal that says "all > > devices have seen the edge". > > Reset is not edge triggered but level signal.
It still has propagation delay. If your XNOR gate connects to the NORAD master launch controller, your design may have side effects. > > > We should either have just 1, or merge 1 and 2. > > > > Then we'd be back to where the problems started. > Sorry, I don't see the problem yet.
