1. Gu Minhao, DAQ group Experimental Center of IHEP February 2011
KM2A data acquisition system software Progress of prototype DAQ and plans for final system
Gu Minhao, DAQ group Experimental Center of IHEP
February 2011

2. Overview DAQ work summary for the prototype Plans for the final system
DAQ system description
Software design
Run of KM2A prototype
Plans for the final system
Requirements
Some plans
Progress of porting Atlas TDAQ

3. Prototype DAQ system description
single VME crate
Data readout from VME backplane
Data transfer to PC through network
Detectors
… …
Switch C P U
Configure
Data (CBLT)
Electronic boards
VME crate PC

4. Prototype DAQ software
Back end control
Configuration
Files
Front end readout
network
Physics
Calibration …
Online histogram
Plugins
Three major components
Front end readout program
Back end control application
Online histogram application
Some plugins designed for a specific type of electronic boards
Electronic Boards

5. Run of KM2A prototype
KM2A prototype has been running since Oct. 2010, taking over 200 runs and more than 150Gbytes of data in Tibet
Backend Control Application
Online histogram

6. Plans for the final system
Requirements
Some plans
Progress of porting Atlas TDAQ

7. Total number of channels
Requirements
Performance requirements for each system
Sub System
Detectors
Total number of channels
Event rate
Data rate
KM2A
5000 electron detectors & 1000 μ detectors
6000
<1KHz
uncertain
WCDA
4 Cherenkov Detectors
900×4
≈16KHz
≈50MBytes/s

8. Other Requirements Remote run control Online monitoring Stability
Online histogram
Event display …
Stability
Common error can recover without human intervention
Fatal failure must be reported to operators in time

9. Plan 1 : Front end readout
Back end
Front end readout
FE Network C P U
Configure
Data (CBLT)
Electronic boards
VME crates
Single Board Computer on VME, Running Embedded Linux system
Data readout through VME CBLT
Maximum throughput: 19MBytes/s (according to DYB experiment)
For WCDA, which data rate is 50MBytes/s, we need at least 3 such crates. KM2A electronics is also designed to use multiple crate for data readout, so we need event building at back end.

10. Plan 2 : Back end: Based Atlas TDAQ
Why?
Its high performance
Its scalability. WCDA and KM2A has different performance requirements for DAQ system. In TDAQ, we can moderate the scale of the DAQ for both systems
It has lots of tools and interfaces for building distributed online monitoring system
It has well designed dataflow method for event building and filtering, that can meet the need of LHAASO
Our experience in porting the TDAQ framework …

11. Progress of porting TDAQ
We have …
adjusted the dataflow implementation to the need of LHAASO
fixed some bugs in TDAQ framework
created a configuration for simulate runs
Back end can run with simulate data currently
Ported TDAQ software running with simulate front end

12. Progress of porting TDAQ
More efforts are still required …
Add components for communication between front end and back end applications
Simplify dataflow components to make the DAQ system more efficient
Design and implement a online monitoring system
Go on with software debug …

13. Conclusions Development of DAQ software for prototypes is almost done
Software for KM2A prototype has successfully run for half a year, and the software for WCDA prototypes is ready now
DAQ & online software development for the final LHAASO project is in progress

14. Thanks for your attention !