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HADES RPC Threshold setting and Temperature/Voltage/Current Monitoring

1. Project status

1.1. Status

2. Introduction

The large scale HADES Experiment at GSI upgrades the new RPC (resistive plate chamber) detector of HADES.
The readout is based upon the TRBv2: General Purpose Trigger and Readout Board (pdf)
Therefore the RPC setup requires control and monitoring elements to set and read two threshold settings for each RPC channel.
In addition 1-Wire© bus based temperature sensors on DAQ boards have to be monitored.
These data are collected via the AXIS' ETRAX FS chip on the TRBv2 board responsible for the DAQ. Since EPICS can be run on ETRAX's cris architectures, EPICS will be used to provide this functionality.
As a further device the proposed Low Voltage Supply Board's temperature, voltages and currents have to be monitored via the ETRAX LX based HADcon(trol) general purpose board module (a.k.a. HADShoPoMo).

2.1. System overview

Picture 1 shows a sketched overview of the system of half a sector to be monitored and/or controlled.

Overview RPC
sketched overview of RPC (click on it to change size)

Overview of one sector of the RPC wall
Overview of one sector of the RPC wall (click on it to change size)

2.2. Persons in charge:

  • Alex Gil, HADES, IFIC (CSIC-University of Valencia)
    • Main worker
  • Elena Castro, HADES, Univ. Santiago
    • Former Main worker
  • Diego Gonzalez-Diaz, HADES, GSI
    • Hardware and RPC support, Mapping Table (⇒ HADES Oracle Database)
  • Juan Garzon, HADES, Univ. Santiago
    • RPC support
  • Peter Zumbruch, EE/KS, GSI
    • EPICS support
      • EPICS on ETRAX
  • Burkhard Kolb, HADES, GSI
    • additional general EPICS support

2.3. Part I: TRB

One of the two tasks of this project is:
  • to control and monitor via EPICS located on the ETRAX FS chip of the TRBv2:
    • for each measuring channel on a daughterboard (DBO)
      • TOF threshold (set)
      • TOT threshold (set)
    • for each motherboard (MBO)
      • one temperature sensor (get)
    • for each TRB board
      • one temperature sensor (get)

Number of channels (thresholds)
thresholds/channel × channels/DBO × DBOs/MBO × MBOs/TRB × TRBs/sector × sectors
2 4 8 4 4 6
thresholds total: 6144

Number of channels (MBO Temperatures)
temperature sensors/MBO × MBOs/TRB × TRBs/sector × sectors
1 4 4 6
MBO temperatures total: 96

Number of channels (TRB Temperatures)
temperature sensors/TRB × TRBs/sector × sectors
1 4 6
TRB temperatures total: 24

temperatures:   thresholds:   Total:  
  120   6144   6264

2.4. Part II: LV module

The other part faces the low voltage. Its task is
  • to monitor via an attached general purpose board HADControl (aka HADSHOPOMO) which itself is based on an ETRAX LX100 chip and therefore also able to run EPICS on it:
    • for each LV module
      • currents of each output connector
        • | Current of + 6 V (× 8 for each output connector -channel A of each ADC sensor-) | (get) |
        • | Current of - 6 V (× 8 for each output connector -channel B of each ADC sensor-) | (get) |
        • | Current of + 4 V (× 8 for each output connector -channel C of each ADC sensor-) | (get) |
      • temperature
        • one temperature sensor (get)
      • dual switch
        • shutdown (set)
        • led status (set)

Number of channels (currents and voltages)
Channels/ADC_chip × ADC_chips/LV Board × LV Board/sector × sectors
4 8 2 6
total: 384

Number of channels (Temperatures)
temperature sensors/LV × LV Board/sector × sectors
1 2 6
temperatures total: 12

Number of channels (Dual switch)
Channels/Dual_switch_chip Dual_switch_chip/LV × LV Board/sector × sectors
2 1 2 6
Channels swith total: 24


3. Interfaces

3.1. Data Formats

3.1.1. TRB Thresholds

3.1.2. TRB Temperature Reading

3.1.3. LV/HADControl Voltage/Current Reading

3.1.4. LV/HADControl Temperature Reading

4. Solutions

4.1. Hardware

4.2. Software

4.2.1. Base System

Since EPICS can be run on ETRAX's cris architectures (q.v. above), EPICS will be used to provide the controls functionality.

4.2.2. Drivers / API TRB Threshold Control TRB Temperature Reading LV/HADControl Voltage/Current Reading LV/HADControl Temperature Reading

4.2.3. EPICS Records TRB Thresholds TRB Temperature Reading LV/HADControl Voltage/Current Reading LV/HADControl Temperature Reading

5. Documentation

5.1. Software

5.1.1. Database Design RPC Threshold settings
Using VDCT (also a web-interface is available) those files document the database design for the threshold settings. They are not (yet) used as templates for creating the database, but instead extracted from one existing set. Functions from rpc_thr.c called in the sub records and their behavior
    • (NOTE: if ToTL is part of some name then ToTR, ToFL and ToFR can replace it)
      sub record Function Action taken
      stToTL myStoreFcn writes single values to one entry of the WRITE/PRESET table
      • if not blocked by entry in FREEZE table
      defToTL setDefaultToT
      writes one value to every entry of the WRITE/PRESET table
      • if not blocked by entry in FREEZE table
      sftToTL setFreezeTable sets a flag for each single channel in the FREEZE table if frozen or not, i.e. if access is allowed or not
      retToTL myRetrieveFcn reads single entries from the READ table
      gpToTL readWriteTable reads single entries from the WRITE/PRESET table
      $(TRB):wT myWriteFcn writes the content of the WRITE/PRESET table to the device
      and copies the content entry by entry to the READ table
      $(TRB):readT myReadoutFcn reads/should read back the device's settings into the READ table
-- PeterZumbruch - 09 Jul 2008

5.1.2. RPC Threshold settings (rpc_thr.c and fs_fpga_int.c) Functions:

  • rpc_thr.c
    • spi_write(struct DataStreamS *dataStream, unsigned long offset, unsigned long mask, unsigned short mode, char *functionname)
      1. read32_from_FPGA into readVal from device_address and offset
      2. clear/set bit in readVal by applying &= mask / |= mask
      3. write32_from_FPGA readVal to device_address and offset
      4. read32_from_FPGA into readVal2 from device_address and offset
      5. Error if readVal !!= readVal2
    • spi_clear
      • spi_write 0
    • spi_set
      • spi_write 1
    • write_one_bit_to_SPI
      • 0: spi_set
      • 1: spi_clear
    • writing_Nbits_word_to_SPI (TYPE word, struct DataStreamS, unsigned int bits)
      • split Nbits word of length bits, up into single bits starting from LSB
        and loop bits times
        1. neg_slope
        2. write_one_bit_to_SPI
        3. pos_slope
    • writing_xyzWord_toSPI (unsigned int type, struct DataStreamS *my)
        • writing_Nbits_word_to_SPI (my→ element, bit size of element)
    • writing_whole_word ( struct DataStreamS *my)
      1. writing_xyzWord_toSPI(DONT_CARE_WORD, my)
      2. writing_xyzWord_toSPI(COMMAND_WORD, my)
      3. writing_xyzWord_toSPI(ADDRESS_WORD, my)
      4. writing_xyzWord_toSPI(DATA_WORD, my)
    • myWriteFcn(subRecord *precord)
      1. init_ports
      2. writing write Table to TRB's MBO SPI chain
        1. loop mbo
          1. loop _channel _
            1. negative_slope_CS
            2. loop dac
            3. set struct dataStream elements: mbo, dac, channel, data_word = thr (calibrated)
            4. writing_whole_word (dataStream)
            5. positive_slope_CS

5.2. Running & Usage

5.2.1. RPC Threshold settings Running Etrax Thresholds Control
-- PeterZumbruch - 14 May 2008

6. Administration

6.1. Minutes

-- PeterZumbruch - 11 Oct 2007

  • Possible appearance of the slow control monitor:
    Possible appearance of the slow control monitor
    Possible appearance of the slow control monitor (click on it to change size)

-- PeterZumbruch - 09 Jul 2008
Topic attachments
I Attachment Action Size Date Who Comment
Database-design-Channels.dbdb Database-design-Channels.db manage 8.6 K 2008-07-09 - 11:34 PeterZumbruch Database design channel-wise
Database-design-Supervisory.dbdb Database-design-Supervisory.db manage 8.8 K 2008-07-09 - 11:35 PeterZumbruch Database design supervisory
EtraxTest.dbddbd EtraxTest.dbd manage 201.9 K 2008-07-09 - 12:36 PeterZumbruch corresponding database definition file
RPC-Overview.pngpng RPC-Overview.png manage 50.1 K 2007-09-10 - 12:15 PeterZumbruch Overview RPC
kickoff-RPC-control.pdfpdf kickoff-RPC-control.pdf manage 179.5 K 2007-09-10 - 12:01 PeterZumbruch scanned meeting minutes of kick-off meeting
slowcontrol_monitor.JPGJPG slowcontrol_monitor.JPG manage 416.9 K 2007-10-10 - 17:08 ElenaCastro Possible appearance of the Slow Control monitor
thresholds.JPGJPG thresholds.JPG manage 424.9 K 2007-10-10 - 14:04 ElenaCastro Overview of one sector of the RPC wall
Topic revision: r21 - 2011-07-14, PeterZumbruch
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