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 this project
scope.
Proposed system architecture
A block diagram of the proposed system is shown above.
- Rear transition module or RTM, (See hardware project).
- RTM connected to the SVEC board via VMC P2 port.
- RTM i/p panel includes visual (LED) diagnosis.
- Connect to White Rabbit via SVEC SFP port.
- 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