An alarm device monitoring and control tool (1, 40) has a radiation transceiver (20) to locally communicate with alarm devices (50) within a building. It generates and transmits test instructions for the devices and receives and processes event data resulting from said instructions. This event data includes historical event data captured by the devices in real time, especially regarding signal strength and repeat levels for communication between individual devices. It can test reliability of wireless communication paths between devices in a group by sampling in the frequency band used to determine interference. Also, it can automatically convert between count values transmitted by a device and a real time stamp, allowing real time patterns to be monitored even though the device has a small processing and memory capacity without a real time clock.