Rapid development of devices with emerging interface standards can be a challenge for even the most experienced designers. Arrow’s SpeedChips simplify this process by offering royalty-free, drop-in solutions that reduce risk and speed time to market. They are available for a growing number of vertical markets where low-cost, chip-down solutions otherwise wouldn’t exist.
One such market Is fault-tolerant, redundant Ethernet networks. The need for products supporting fault tolerant Ethernet protocols such as High-availability Seamless Redundancy (HSR) and Parallel Redundancy Protocol (PRP) is growing in systems where network resiliency must be maintained during single fault scenarios and system maintenance.
Introducing Arrow’s SpeedChips XRS7000 Product Family
Arrow is proud to introduce the first product in its line of SpeedChips products, the XRS7000 series HSR/PRP enabled single-chip gigabit Ethernet Switches. As the first off-the-shelf HSR/PRP gigabit Ethernet chips in the world, these devices allow increased availability and reliability in network connections. Integration into your product lowers the total cost of ownership as a separate RedBox (redundancy box) is not required. In addition to supporting both HSR and PRP implementations, the chips also feature Precision Timing Protocol (PTP) to allow nanosecond level time synchronization throughout the network without the need for discreet GPS solutions at each node. The chips offer either two (XRS7003) or three (XRS7004) RGMII interfaces for optical or wired gigabit Ethernet and support RMII, MDIO, and I2C interfaces to a host processor. The XRS series also implement the features of standard Gigabit Ethernet switches, including Rapid Spanning Tree Protocol (RSTP), Quality of Service (QoS), Port-based Virtual LANs, 802.1x security, and more. Table 1 lists the features and associated benefits for the XRS7003 and XRS7004 ICs.
Table 1
Applications
The primary applications for Arrow’s XRS series HSR and PRP switches are in electrical utility substations and smart grids, industrial automation and motion control, transportation networks, and military applications.
Electrical utilities were early adopters of HSR/PRP networks and represent some of the largest installations. Substation Ethernet implementations often use IEC 61850 based networks which require Station and Process Busses, and each of these require protocols like HSR or PRP to ensure uninterrupted flow of data on the bus. Grid modernization is the other primary utility application, as upgrading from switched circuits to Ethernet in utility grids allows utility companies to obtain lower cost services with higher bandwidths. HSR and PRP provide the zero down time redundancy that is critical in these networking applications, and optical interconnects enable this transition while remaining immune to the strong electric fields that can cause safety concerns or degraded performance in analog switched circuits. Implementing gigabit Ethernet in these upgraded circuits adds flexibility, as the higher bandwidths enable additional monitoring and control functions to further enhance the functionality of the Smart Grid. Troubleshooting is also easier compared to serial switched network topologies.
Industrial automation is one of the other key implementation points for HSR and PRP networks. The oil, gas, and mining industries rely heavily on high bandwidth, fault tolerant industrial Ethernet networks to provide real-time monitoring and control of critical systems. This allows safe and efficient operation in harsh environments like offshore oil platforms, geographically distributed areas such as oil or gas pipelines, and other hazardous installations like refineries, mines, and processing stations. HSR/PRP networks also enable rapid and coordinated responses to events when they occur, thereby helping to reduce and control risks to people and property. In complex industrial motion control systems like automated production lines, the use of HSR or PRP networks with PTP allows the network to reliably provide the control signals it needs to continue production even during single-fault failures in the network.
Transportation networks are another beneficiary of the features of HSR and PRP networks, whether they are vehicle based or part of the supporting transportation infrastructure. Gigabit Ethernet is quickly becoming necessary in these networks due the combined bandwidth needs of diagnostic and control data, video surveillance data, and multimedia passenger information. When paired with HSR or PRP, the result is a fast and reliable network that helps ensure passenger safety and system reliability.
Military systems present one of the most intuitive applications for HSR and PRP networks as the need for reliable information flow and command and control channels is ubiquitous in the military. Fault-tolerance is needed in all scales of network complexity to ensure proper system operation in the most challenging conditions, due to the severe consequences that could occur if equipment stops operating as intended.
Reference Board
Arrow has released the XRS7000 Reference Board to assist in evaluating and implementing the XRS7003 and XRS7004 into devices intended for the applications described above. The reference board is designed to directly interface to a credit-card sized Raspberry Pi Gen 2 Model B single-board computer, or other types of CPU boards can be attached via customized cables. Three HSR/PRP Ethernet ports are available, as well as a CPU Ethernet port, JTAG and GPIO connectors for the XRS7000 series IC, a PPS timing port, and a 5V power input.
The CPU port is located on the bottom of the reference board and features power and ground, Power_OK, two MDIO interfaces, an I2C interface, and active low Reset and Interrupt lines. The power and ground ports can be used to power the Raspberry Pi CPU board with 5V, or to power the XRS7000 evaluation board from the Raspberry Pi power source. The two MDIO interfaces provide access to the registers of the XRS chip and the Marvell and TI Ethernet PHYs. The I2C interface also provides register access to the XRS chip as well as interfacing with the registers on the SFP modules via an NXP I2C expander chip.
The three HSR/PRP gigabit Ethernet ports are available through either RJ45 connectors or SFP modules. The SFP interfaces support both optical and wired modules, and are prioritized if both SFP and RJ45 copper media are connected on the same port. Interface speeds are typically defined by the module used, but if the module can be configured via register settings, a multiple speed module can be used. The copper Ethernet interfaces use standard RJ45 connectors and support auto crossover and auto-negotiation to 10/100/1000 Mbit/s speeds.
The reference board’s JTAG and GPIO connectors interface to the installed XRS chip. Seven GPIOs are available and each can be independently configured as an input our output.
The PPS timing interface provides a 1 Hz, 20us long pulse output, and accepts either event-based pulses or synchronization pulses from an external timing source up to 25MHz.
Reference software for the board is available, and targets the Raspberry Pi 2 Model B. The Raspberry Pi 1 Model B+ is also supported, but has less processing power.
If your product needs the fault tolerance of High-availability Seamless Redundancy or Parallel Redundancy Protocol at gigabit speeds, Arrow’s XRS7000 series of SpeedChips devices offer a feature rich, drop in solution that will greatly reduce project risk and design costs and allow you to rapidly bring your product to market.