The PCI bus requires that every time the device driving a PCI bus signal changes, one turnaround cycle must elapse between the time the one device stops driving the signal and the other device starts. Without this, there might be a period when both devices were driving the signal, which would interfere with bus operation.
the pci bus requires that every time the device driving a pci bus signal changes one turnaround cycle must elapse between the time the one device stops driving the signal and the other device starts without this there might be a period when both devices were driving the signal which would interfere with bus operation