optimize the sleep time for ATM stable.

default sleep time = 1 sec
-> too long to do calibration with atm_calib2 ...

change the sleep time & trigger rate

- # of events = 1000
- Q = 50 pC
- T = 0 nsec

1. 100 msec, 1Hz
file : atm_calib2_1.root
-> data tree was not shored...

2. 100 msec, 5Hz
file : atm_calib2_2.root
-> data tree was not shored...

3. change NIM logic
before : trigger -(10usec)-> accept -(200usec)-> request
after  : trigger -(1msec)-> accept -(200usec)-> request

100 msec, 5Hz
file : atm_calib2_3.root
-> data tree was not shored...

re-measurement
(NIM logic is not changed from 3.)

- # of events = 1000
- Q = 50 pC
- T = 0 nsec

1. 100 msec, 1Hz
file : atm_calib2_1.root
time = 1.0043 sec

- Hit of only A channel due to rate is slow...
(AD convert is complete before next trigger)

2. 100 msec, 10Hz
Try to run with max daq rate. VETO is active until pedestal run end 
(100 msec sleep = 10Hz)

- Hit of only A channel. => need pre-scaler
- time / cycle = 204 ~ 206 msec -> max rate < 5Hz

3. 100 msec, 4Hz
check stability
file : atm_calib2_3.root

- Hit of only A channel due to rate is slow...