  A new $\mu$TCA DAQ system was introduced in CANDLES experiment with
SpaceWire-to-GigabitEthernet (SpaceWire-GigabitEthernet) network for data
readout and Flash Analog-to-Digital Converters (FADCs). With
SpaceWire-GigabitEthernet, we can construct a flexible DAQ network with
multi-path access to FADCs by using off-the-shelf computers. FADCs are equipped
8 event buffers, which act as de-randomizer to detect sequential decays from
the background. SpaceWire-GigabitEthernet has high latency (about 100 $\mu$sec)
due to long turnaround time, while GigabitEthernet has high throughput. To
reduce dead-time, we developed the DAQ system with 4 "crate-parallel" (modules
in crates are read in parallel) reading threads. As a result, the readout time
is reduced by 4 times: 40 msec down to 10 msec. With improved performance, it
is expected to achieve higher background suppression for CANDLES experiment.
Moreover, for energy calibration, "event-parallel" reading process (events are
read in parallel) is also introduced to reduce measurement time. With 2
"event-parallel" reading processes, the data rate is increased 2 times.
