1. RPC Configuration
DataBase
Pierluigi Paolucci - I.N.F.N. of Naples

2. Pigi Paolucci, I.N.F.N. of Naples
RPC Barrel
I.N.F.N. Naples
HV system  ~ 480 channels
config. param. = 8
cond. param. = 11
LV system  ~ 750 channels
Temperature  ~ 300 channels
Front End  ~ 4680 Front-End Boards
config. param. = Threshold & Width
cond. param. = Rate/Occupancy histograms
30/05/2019
Pigi Paolucci, I.N.F.N. of Naples

3. 9.360 Threshold + 9.360 width + 4.680 temp.
Front-End Board Data
I.N.F.N. Naples
Barrel FEB is equipped with 2 front-end chips (8 strips each) and 1 temperature sensor. For each chip there are:
2 threshold value (hardware defaults of 200 mV);
2 width values (hardware defaults of 100 ns);
1 temperature value.
How many operations/bytes do we need to read/write this parameters ??
Read width/thresh.  2 write + 1 read  5 bytes
Read temperature  2 write + 1 read  5 bytes
Write width/thresh.  3 write  6 bytes
TOTAL number of FEB parameters are
9.360 Threshold width temp.
30/05/2019
Pigi Paolucci, I.N.F.N. of Naples

4. RPC Barrel configuration Data
I.N.F.N. Naples
Barrel RPC detector is equipped with 480 HV channels and with 780 LV channels.
To configure the detector we need to set:
Vset, Vmax, Iset, Imax, Trip, Rup, Rdown, On/Off.
HV & LV configuration requires about
1260 ch * 8 par. = par * 2 bytes = 20 KB
FEB configuration requires about
3.4 Kbytes per Link Board
corresponding to 2 MB.
30/05/2019
Pigi Paolucci, I.N.F.N. of Naples

5. RPC configuration states
I.N.F.N. Naples
The RPC detector will have 4 different states (run, calibration, “injection/safe” and off);
RUN  LVON && HVON (status = = working voltage) && FEBThresholdLoaded && NoiseRateOK
SAFE  HVON (status = = safe voltage)
CALIBRATION  LVON && FEBThresholdLoaded && NoiseRateOK && different voltages.
“Plateau calibration” needs 5-7 runs with different configuration parameters (HV set-points) when the others muon systems are working/triggering in “normal mode”.
RPC must be in local mode and the RPC Local DAQ will take data.
Offline monitoring to calculate the efficiency curves.
Noise calibration runs needs few runs with different FEB thresholds but fixed HV set-points.
30/05/2019
Pigi Paolucci, I.N.F.N. of Naples

6. Front End Board Summary
I.N.F.N. Naples
RPC/FEB monitoring requires about
100 Bytes/s per Link Board
corresponding to 60 KB/s in the barrel.
FEB configuration requires about
3.4 Kbytes/s per Link Board
corresponding to 2 MB/s in the barrel.
30/05/2019
Pigi Paolucci, I.N.F.N. of Naples

7. 128 strips * 2 counters * 32 bits = 8 Kbits/10s = 100 Bytes/s.
Front End Board Data III
I.N.F.N. Naples
Additionally for the orbit synchronization there are ca bit counters (1 for each bunch crossing) producing ca. 128 Kb of data / plot. But these probably can be read less often.
The theoretical throughput of a CCU chain (up to 27 CBs) is 4 MB/s.
The theoretical throughput of a LB box is 4 MB/s / 27 = 152 KB/s.
The theoretical throughput of a Link Board is 152 KB/s / 8 = 19 KB/s.
Required throughput for a continuous monitoring of one RPC is:
128 strips * 2 counters * 32 bits = 8 Kbits/10s = 100 Bytes/s.
The I2C communication does not contribute significantly to the total CCU load.
The total bandwidth depends on the number of CB's in single CCU chain (serviced by a single FEC).
30/05/2019
Pigi Paolucci, I.N.F.N. of Naples

8. Pigi Paolucci, I.N.F.N. of Naples
Front End Board Data II
I.N.F.N. Naples
The front end electronic boards communicate with the Link Board through the I2C bus;
Each Slave LB receives data from up to 6 FEBs  96 strips;
Each Master LB is connected to not more than 2 SLB;
MLB transmits data to the control room via optical fiber;
Each LB crate house up to 8 LBs and has 1 Control Board (CCU);
The RPC continuous monitoring (noise rate, occupancy…) will have a refresh rate of 10 sec;
For each strip the events before and after windowing are counted during a defined period of time. That allows plotting of rates and efficiency;
There are two 32-bit counters for each group of 128 channels/strips;
The amount of data to be sent is 2*32*128 = 8 Kb/10s/LB/plot.
30/05/2019
Pigi Paolucci, I.N.F.N. of Naples