The detector utilizes a QuarkNet DAQ Card running firmware version 3.2. The small paddles for efficiency monitoring are connected to channels 1 and 2, while the large panels are connected to channels 3 and 4. The threshold on channels 3 and 4 was lowered to 15mV because of signal differences from the large panel.
Traditionally, the DAQ card transmits data about every channel during every hit. However, the rates of this detector exceeded the bandwith of the serial interface. Thus, the CPLD on the board was reprogrammed so that the scalars display the following quantities:
(Channels listed as 1-4 instead of 0-3 for consistency)
S4: 3 and 4
S0: 1 and 2 not 3 not 4
S1: 1 and 2 and 3 not 4
S2: 1 and 2 not 3 and 4
S3: 1 and 2 and 3 and 4
Note: A special thanks to Terry Kiper and Sten Hansen for all of their help in customizing the DAQ
The DAQ card is connected to a Linux machine by serial port. The computer is running a program written in Python that reads the scalars, as well as temperature and pressure data, at 5 minute intervals. The data is then posted to the internet.