EPICS MCA Amptek Driver

Contents

• Overview
• Hardware configuration
• Software architecture
• medm screens
• Startup script
• Restrictions

Overview

This is an EPICS driver for the EPICS mca module that supports the DP5 series MCAs from Amptek (Ametek). These include:

• The digital pulse processing MCAs integrated into the X-123 CdTe, SDD, and Si-PIN detectors
• The standalone PX5 digital pulse processing MCA and power-supply
• The MCA8000D standalone MCA which works with analog pulse shaping electronics

The driver supports both MCA (spectrum) mode, and MCS (multi-channel scaler mode) which produces counts in a user-defined spectral Region-Of-Interest as function of time.

The DP5 MCAs support USB, Ethernet, and RS-232 communication. This driver currently supports USB and Ethernet, and these have both been tested on both Linux and Windows. RS-232 is much slower and seems to offer no advantages compared to Ethernet and USB, but support for RS-232 could be added in the future.

Hardware configuration

When using Ethernet the DP5 MCA can be configured either for DHCP or fixed IP address. If using DHCP then one can determine the actual IP address in use in two ways.

1. Use the DppMCA Windows program from Amptek. Press the "Find DP5 IP" button. That should show you what IP address the module has. Press the "Connect" button. You should now be able to control the detector over Ethernet.
2. Run the IOC using an arbitrary IP address for the module in the drvAmptekConfigure() command. The IOC application will list the IP addresses of all Amptek DP5 modules that it finds on the local subnet.

To configure the DP5 to use a static IP address use the Firmware Manager software from Amptek.

When using USB with a single DP5 MCA, the serial number does not have to be specified (i.e. can be left blank). If there are multiple DP5 MCA, you should specify the device you want to connect to by the serial number, otherwise the first DP5 MCA to enumerate will be connected. The serial number should be on a label on the chassis. It can also be found by repeating the following for each DP5 MCA:

1. connect a single DP5 MCA (disconnect or power down the others)
2. run mcaAmptekApp with a single mca record without specifying a serial number
3. caget $(P)$(R)SerialNumber

or by looping though the following with values of $(index) from 1 to the number of detectors plugged in and powered up:

1. running amptekTest2 -d $(index)
2. look for the serial number in the output

Software architecture

The driver inherits from asynPortDriver, which is part of asyn. The driver uses the standard device-independent asyn device support for the MCA record. The INP link is of the form INP=@asyn(PORT, 0), where PORT is the name of the asyn port that has been created with the drvAmptekConfigure() command.

In addition to the functions supported by the MCA record, this driver has additional functions supported by records in the Amptek.db database. These records correspond to the parameters documented in the DP5 Programmer's Guide. This database contains the following records:

medm screens

The following shows the MEDM screen for the Amptek control

Amptek.adl with PX5 and XR-100SDD detector

The following shows the MEDM screen for the Amptek single channel analyzer (SCA) configuration

Amptek_ROI_SCA8.adl with PX5 and XR-100SDD detector

The following shows the MEDM screen for the MCA display with a PX5, XR-100CdTe detector and a Cd109 radioactive source

mca.adl

Startup script

The mca/iocBoot/iocAmptek contains example startup scripts for the Amptek detectors.

The command to configure the Amptek driver is drvAmptekConfigure().

int drvAmptekConfigure(const char *portName, int interfaceType, const char *addressInfo, int directMode)
  The arguments are:
      portName:            # The name of the asyn port to be created
      interfaceType:       # The interface to use: 0=Ethernet, 1=USB, 2=RS-232
      addressInfo          # The device address information. 
                           # For Ethernet this is the IP address of the module.
                           # For USB, this argument may be the serial number
                           #   or left blank for the default unit.
                           # RS-232 is not currently supported.
      directMode:          # Enable broadcast-less connection: 0=use broadcast,
                           #   1=skip broadcast

Restrictions

The driver currently has the following restrictions. These may be addressed in future releases.

• The driver only works on Linux and Windows because these are what the vendor library supports. The software could be modified to the the EPICS libCom library, and then it could work on other operating systems such as vxWorks.
• The following configurations have been tested:
  • PX5 with XR-100-CdTe
  • PX5 with XR-100-SDD
  • X-123CdTe
  • X-123SDD
  The MCA8000D will probably work, but will likely generate many error messages since it does not support many of the parameters that EPICS controls.
• Only the Ethernet and USB interfaces are currently supported. RS-232 may be supported in the future, but it is much slower than Ethernet and USB, and offers no clear advantages.
• When using Ethernet and exiting the IOC one must wait at least 20 seconds before starting it again. This is the time the DP5 requires to "forget" the previous connection.
• The driver only provides EPICS records to control a subset of all of the DPP parameters. The following parameters cannot currently be controlled by EPICS:
  • Baseline restorer (BLRD, BLRM, BLRU)
  • Power-on state (BOOT)
  • List mode (CLKL, LMM0, SYNC)
  • Non-trapezoidal shaping (CUSP)
  • DAC control (DACF, DACO)
  • General purpose counter (GPED, GPGA, GPIN, GPMC, GPME)
  • Input offset (INOF, INOG)
  • Preamp control (PAPS, PAPZ)
  • Peak detect mode (PDMD)
  • Reset configuration (RESC)
  • Reset lockout interval (RESL)
  • Risetime discriminator control (RTDD, RTDE, RTDS, RTDT, RTDW)
  • Digital scope control (SCOE, SCOG, SCOT)
  • Scintillator time constant (SCTC)
  • Spectrum offset (SOFF)
  • Lower level discriminator (TLLD)
  • Test pulser mode (TPMO)
  • PX5 speaker (VOLU)
  Note that while EPICS cannot directly control the above parameters, they can be controlled by manually editing a configuration file and then using the EPICS driver to upload that configuration file to the device. It would not be difficult to add support for these parameters if there is a need in the future.