Difference between revisions of "Compton DAQ Dev"

Revision as of 15:30, 14 October 2022

Here are some notes on the project of developing the Compton counting mode DAQ. The original work was done mainly by Bryan Moffit and Ben Raydo in 2020, with input from others.

It is foreseen to be a precurser of a moller polarimeter DAQ as well as a counting-mode DAQ for the MOLLER project, etc.

See earlier work https://hallaweb.jlab.org/wiki/index.php/Compton_Counting_DAQ_Software_HOWTO

Budget and Plan

          Budget and Plan

 Upgrade of Compton and Moller polarimeter DAQ in halls A and C.

 The 4 systems are approximately the same.  The FADC will be modified
 to support both counting mode and integrating mode.  

 Item      Price each      Qty       Line cost

 VXS crate   16.5 k        4         66 k
 VTP         10 k          4         40 k
 FADC (was not in budget)
 cpu (ATOM)   3 k          4         12 k
 SD           2 k          4          8 k
 scaler       4 k          4         16 k
 VETROC       2 k          8         16 k
 TI           2 k          4          8 k
 I/O          1.5 k        4          6 k
 Spares                              43 k
 ==========================================
 TOTAL                              215 k$
 
It's essentially 43k$ per DAQ (times 5 since we need spares)
except we must scrounge the FADCs.  We'll buy the first system
for the hall C moller in FY2023.  This 43k$ is in the FY2023 budget.
After that we may need to refine the design.  Then in FY2024 we'll
purchase/build 3 more DAQs.  Finally, buy spares in FY2025.

Documents

VTP manual https://userweb.jlab.org/~rom/compton/VTP-Manual.pdf

Compton Trigger https://userweb.jlab.org/~rom/compton/Compton_Trigger_2020.pdf

Current Test Setup

updated R. Michaels Oct 12, 2022

Here is a picture https://userweb.jlab.org/~rom/compton/polarimeter_daq.xfig.pdf

The basic configuration of the DAQ

DAQ config: https://userweb.jlab.org/~rom/compton/haVTP_config.png

ROC1 : https://userweb.jlab.org/~rom/compton/roc1_config.png

VTP : https://userweb.jlab.org/~rom/compton/vtpROC_config.png

How to Run the Current Setup

This is a VXS crate located in the TEDF building cubicle 11. The crate is at the top of the rack. The crate was formerly installed in hall A during PREX/CREX.

updated Oct 12, 2022.  R. Michaels

How to login to the two ROCs and start the ROC

ssh -X amoll1 -l sbs-onl
./startroc1

ssh -X havtp1 -l sbs-onl
./startRoc

How to start CODA on atedf3.  Username adaq.

kcoda

startcoda

VTP readout
havtp1:/home/sbs-onl/comptonDaq/vtp/rol/vtp_list.so
ROC1 readout
amoll1:/home/sbs-onl/comptonDaq/rol/vtpCompton_list.so

Oct 12, 2022.
Currently using a 50 Hz front-panel pulser trigger on TI.
Later want to modify this to use a trigger from VTP based on data
from FADC and/or the VETROC.

If I drop the VTP from the readout and remove tiRocEnable(2)
from amoll1:/home/sbs-onl/comptonDaq/rol/vtpCompton_list.c
then the DAQ runs fine and both the FADC and VETROC data
make sense.

Next I added the VTP.  Still a FP trigger.  It downloads
and prestarts. But here is where the problems start. 

Current Problems

Oct 13, 2022, see update Oct 14 below.  R. Michaels

Yesterday a problem was overcome: wrong firmware.
vtpInit: VTP_FW_Version=0x10004, VTP_FW_Type=19
VTP_FW_Type 19 is the SoLID ECAL test firmware, needed 15 for Compton.
Ben fixed it by editing
/usr/local/vtp/params/firmwares/vtp_firmware.txt

Problematic symptoms today:

Considering the VTP vtp_list.c

Running the DAQ with a 50 Hz pulser for the FP TI input.

With the following default combination 

     #define USE_DMA
     #define READOUT_TI
     #define READOUT_VTP

The DAQ was limited to 1.5 Hz.  The VTP produced 10 words which
were featureless (always the same numbers).  I don't know what
the VTP should produce.

Using the following, all components ran at 50 Hz, but it's just info,
it's not what we want.

    #define USE_DMA
    #define READOUT_TI
//  #define READOUT_VTP

Using the following, all components ran at 50 Hz, but the code did not
compile, as is.  I had to replace gpDmaBuf (undefined anywhere) with pBuf.  
It seemed to be what we wanted, but I'm not sure. 

//  #define USE_DMA
    #define READOUT_TI
    #define READOUT_VTP

However, every event produces a timeout.  Printouts on the havtp1 ROC:

   {vtpEbTiEventReadErrors=1}
   {vtpEbEventReadErrors=8051}
   vtpEbReadEvent: TIMEOUT ERROR (cnt=8052)  

the 8051 and 8052 increment with each event.

Questions, partially answered.
Questions

1. What data is the VTP supposed to produce ?
   I suppose it is "diagnostic event data" to confirm trigger decisions.

Answer is basically yes.  Ben gave me the doc VTP_trigger.pdf (see Documents).


2. What causes the data to be ready ?
   Perhaps I am missing a link.

When the VTP ROL gets the trigger ready signal (from a link it has to the TI, it polls a register) it starts 2 DMA transfers: one for the TI event info (see READOUT_TI in vtp_list.c) and another for the VTP firmware specific event info (see READOUT_VTP also). Then the ROL waits for the TI DMA engine to finish (indicating an event was fully ready or there was  a timeout) and then the same thing follows for the VTP event.

I need to check which register and see how it gets set.

3. Where is vtpEbTiReadEvent defined ?  I did not see it
   in the library.

Ok, I have inconsistent libraries.  It would be nice to have the sources 
for the library that is actually used.  I'll search around on github.

[sbs-onl@havtp1 ~]$ nm $CODA/Linux-armv7l/lib/libvtp.so | grep vtpEbTiReadEvent
00024914 T vtpEbTiReadEvent
[sbs-onl@havtp1 ~]$ 
[sbs-onl@havtp1 ~]$ nm /home/sbs-onl/comptonDaq/vtp/libvtp.so | grep vtpEbTiReadEvent
------- nothing ^^^^ -------

[sbs-onl@havtp1 ~]$ nm $CODA/Linux-armv7l/lib/libvtp.so | grep vtpEbTiReadEvent
00024914 T vtpEbTiReadEvent
[sbs-onl@havtp1 ~]$ nm /home/sbs-onl/comptonDaq/vtp/libvtp.so | grep vtpEbTiReadEvent


4. Is there a special significance to gpDmaBuf and where is
   it defined ?

A bit of a mystery, but I htink it's similar to 3.  The sources I have are inconsistent.

Update Oct 14

I'm told I should use the library in /home/sbs-onl/comptonDaq/vtp/libvtp.so
instead of /mnt/SBS/coda/3.10_arm/Linux-armv7l/lib/libvtp.so and that the VTP ROL
should use vtpTiLinkReadEvent instead of  vtpEbTiReadEvent.   BTW, I was also
forced to use  vtpTiLinkResetFifo(0) instead of vtpEbResetFifo().
Got vtp_list.c to compile and download but it segfaults in Prestart,
somewhere around where it reads the parameters.  Sigh!  Tomorrow's another day.


---------------------------------------------------------------------------------

Analysis Software

Nothing here yet. Work in progress. But there was software for the DAQ used during PREX/CREX.

Old Results

• Background information: "https://userweb.jlab.org/~rom/Compton_info"
• Results from PREX/CREX "https://userweb.jlab.org/~rom/Compton_ML" (me bored during pandemic)
• Older Material "https://userweb.jlab.org/~rom/compton_old"