The Mesytec MVLC is an intelligent VME crate controller. Like the VMUSB, it is capable of autonomously executing a stack (list) of operations in response to a trigger. What distinguishes the MVLC from the VMUSB, is:
The ability to perform complex trigger decisions to trigger stack execution.
Additional stack operations that allow more complex VME operations to be performed in stacks.
An Ethernet interface in addition to the USB interface provided by the VMUSB.
While Mesytec does not provide sufficient documentation for fully homegrown support of the MVLC, the software support in their github repository (http://github.com/flueke/mesytec-mvlc) for the user mode does provide a skeleton for a readout program. We have forked that repository, and created a modified version of that readout program and contributed it back to Mesytec.
The framework we adapted requires a static configuration file which is read once when the program starts. This configuration file desribes trigger conditions, initialization operations and stacks to execute in response to triggers.
At the FRIB in the bookworm and later containers, the driver software, along with our readout program, is installed in /usr/opt/mesytec-mvlc/version. Where version is a version number such as 0.1.0. Within that directory tree, the readout program is in bin/fribdaq-readout.
Coupled with this program, FRIB/NSCLDAQ 12.2, and later, provides a program $DAQBIN/mvlcgenerate, which can translate many VMUSBReadout daqconfig.tcl configuration files into the configuration files expected by fribdaq-readout
So, to summarize, to use the Mesytec MVLC with FRIB/NSCLDAQ you will need:
An installed version of the Mesytec MVLC driver software buit with support for FRIB/NSCLDAQ readout (more about how to get that from scratch later in this chapter).
A VMUSB daqconfig.tcl with devices supported by the mvlcgenerate program.
Version 12.2 of FRIB/NSCLDAQ or higher, which provides the mvlcgenerate program.
Use mvlcgenerate to translate a daqconfig.tcl written for the VMUSB. This may require small modifications, however those modifications can be made in a way that the resulting configuraion file can be used with both the MVLC and the VMUSB controllers.
Run fribdaq-readout specifying the configuration file that mvlcgenerate created. See fribdaq-readout to see how to use this program. Note that while this program is not yet supported by the ReadoutShell GUI, or managed expermiment, support for both is planned.