VMR-DIO-24CH-DCI project
Project Description
Overview
The aim of this project is to distribute dry contact input signal states
across a wide geographical area, using an Ethernet-based White Rabbit
(WR) network.
The proposed hardware system will acquire these input signals using a
rear transition module or RTM. Transmission through the network will be
managed by the exisiting SVEC
board.
Development of necessary SVEC Gateware is in the scope of this
project.
Proposed system architecture
A block diagram of the proposed system is shown above.
- Rear transition module or RTM, (See hardware project).
- RTM input panel includes visual (LED) diagnosis.
- RTM connected to the SVEC board via VMC P2 port.
- Communication via White Rabbit managed by the SVEC.
- New Gateware for SVEC RTM read, SVEC to WR (Tx) and WR to SVEC (Rx).
Functional description of system components
- LEMO 2-pin connector for dry contact inputs (DCIs).
- 24VDC power supply, complying with industrial environments standards.
- Input protection against voltage spikes or power surges.
- Diagnostic tools to detect faulty inputs: LEDs for visual ON/OFF diagnosis.
- Robust fail safe operation: The rest of the system needs to be aware of failure of any of the components in the acquisition chain.
- No stringent timing requirement, as input required every ~ 1s.
For the SVEC
- Host the RTM:
- Detecting its presence and power status.
- Reading out the dry contact input states in one of the 40 user-defined inputs of the VME P2 port.
- Transmitting signals:
- Send the dry contact input states in the form of Ethernet packets.
- Design decisions will be made on whether transmission is synchronous or asynchronous (transmit periodically or only upon status change).
- Connect to VME host processor:
- Manage a control data path which will be used for network diagnosis (determine LIVE node status).
- Receive gateware upgrades.
- Manage and safeguard WR node identity and location in the event of hardware replacement.
Project Information
This project is divided into three separate projects:
Project documentation can be found at these locations:
- Current projected timeline can be found here.
- CERN-specific information
- Frequently Asked Questions
Status
Date | Event |
2011 | Initial discussions about replacing the external conditions system |
01-10-2015 | Start working on project. |
05-11-2015 | OHWR project page created. |
Denia Bouhired-Ferrag - Erik van der Bij - 12 Novembre 2015