PICMG makes a point to prepare for the future
Author: EIS Release Date: Jul 27, 2022
At last month’s Embedded World, the PCI Industrial Computer Manufacturer’s Group announced plans to update the MicroTCA and new specifications for COM-HPC. By Caroline Hayes.
PICMG makes a point to prepare for the futureThe PCI Industrial Computer Manufacturer’s Group (PCIMG) is updating the MicroTCA specifications to meet evolving demands in the industrial, medical, science, aviation and transportation markets. As applications increasingly implement artificial intelligence, machine learning and cloud access, as well as the next generation of processors, they need increased bandwidth for processing-intensive tasks, such as signal detection in autonomous systems.
The MicroTCA Working Group has begun work on the next generation of architecture specifications.
As well as bandwidth, it will target improvements for time-sensitive and high-bandwidth applications, such as in high energy physics.
It is also looking at the architecture that accommodates the next generation of CPUs and FPGAs that will natively support PCIe Gen 5, which doubles the data transfer speed compared to PCIe 4.0. It will deliver 32GT/s with an aggregate x16 link bandwidth of 128GB/s.
Future applications in industry require this higher bandwidth for image processing, signal detection and data acquisition, said PICMG. Current CPU speeds are limited by 80W per slot, which has prompted the support for more power in the specification review.
Next generation architecture
PICMG also said that future applications will require other kinds of high- and low-speed fabrics paired with more flexibility in system design. One example of this is in the science sector, where high frame rate Mpixel detectors of photon experiments require higher throughput.
All these demands are scheduled to become part of the new releases of these successful specifications. With all these improvements MicroTCA continues to be a pro-active specification with significant updates to support high-bandwidth backplane interconnects. The previous update of the specs was in 2020.
Heiko Koerte, vice-president and director of sales and marketing of NAT, leads the PICMG committee with Kay Rehlich of DESY and Thomas Holzapfel from powerBridge. Koerte comments that the new specification will be used in “many different vertical markets due to the flexibility of MicroTCA”.
Industrial automation, medical, telecommunication, networking, aerospace and transportation applications will benefit from the new performance parameters and by how easily MicroTCA can be adapted to specific needs, he said.
Updates to COM-HPC
At Nuremberg, PICMG announced two new specifications for the Computer-on-Module standard, COM-HPC.
The first is to add support for FuSa (functional safety) applications, such as autonomous vehicle systems. This COM-HPC version defines signal pinouts for applications such as safety-critical machine control, robotics, vehicle and transportation control hardware and avionic equipment. The nature of these weight- and size-sensitive applications means that developers are looking to keep form factors small by using credit card-sized modules.
Some chipsets or SoCs incorporate a FuSa ‘safety island’, which is a separate portion of hardware that monitors the health and status of the main chipset or SoC. It reports any findings over dedicated general purpose I/O and serial peripheral slave interface to an external carrier based FuSa system safe state agent (and optionally a safety controller). The FuSa safety controller is a carrier-based microcontroller that collects safety and status information from the safety island over a dedicated serial peripheral interface (SPI) bus and processes it for external use. The safety controller is the FuSa SPI master.
According to PICMG, connected device developers want to use x86 processor technologies for mixed-critical applications on multi-core processors. This requires redundancy and the possibility of implementing fail-safe processes.
The addition of functional safety extensions in embedded Computer-on-Modules for high performance computing will find applications using an IoT and industry 4.0 gateway, such as collaborative robotics and autonomous logistic vehicles, as well as autonomous driving systems, agricultural and construction machinery. It will also extend to air and sea with autonomous underwater vehicles and unmanned aerial vehicles.
The functional safety extensions are supported across all COM-HPC form factors (see text box). They also apply to the second announcement from PICMG, the COM-HPC Client Mini specification.
This defines the use of a single connector instead of the two implemented for the larger modules (sizes A to E). There are still 400 signal lanes in the specification, which is 90% of the capacity offered by COM Express Type 6 modules.
The specification also halves the footprint, compared to COM-HPC Client Size A modules, the smallest available COM-HPC form factor, with dimensions of 60x95mm.
This makes them suitable for embedded computer logic in space-constrained but high performance top-hat rail PCs for control cabinets in building and industrial automation, or portable test and measurement devices.
The specification allows developers to integrate PCIe 4 and PCIe 5 into small processing units. The specification is expected to become the high-end standard extending the earlier COM Express Mini standard.
Micro Telecommunications Computing Architecture
The Micro Telecommunications Computing Architecture (MicroTCA) was developed by the PCI Industrial Computer Manufacturer’s Group (PICMG) and ratified in 2006. The modular, open standard specifies the electrical, mechanical, thermal and management specifications required for a switched fabric computer system using advanced mezzanine cards connected directly to a backplane.
The standard, as the name implies, is intended for smaller telecom systems – the AdvancedTCA standard addresses larger, high capacity systems. MicroTCA uses the same basic interconnect topologies and management structure as AdvancedTCA, adapted for use in cost sensitive and physically smaller applications with lower capacity, performance, “and perhaps less stringent availability requirements”, according to the original proposal.
Today, it is used outside the telecom market, in defence and avionics, for example.
The latest update to the architectures was the MicroTCA.0 Revision 2.0 in 2020 to the base specification (MicroTCA.0), which defines the electrical, mechanical, thermal and management characteristics:
* MicroTCA.1 added ruggedisation and forced-air cooling.
* MicroTCA.2 allowed for both air and conduction cooling with expanded shock, vibration and temperature operation.
* MicroTCA.3 increased the compliance threshold for shock, vibration, and temperature and requires the use of conduction cooling.
* MicroTCA.4 adds application-specific rear transition modules to improve RF filtering, signal condition and I/O.
MicroTCA is used for precision timing and synchronisation equipment at particle accelerators including CERN, DESY, ESS, XFEL, KEK and SLAC. Its architecture and features are consistent with the modular open systems approach being adopted as part of the US Department of Defense electronic media acquisition policy.
COM-HPC
COM-HPC is designed to complement COM Express and is primarily designed for embedded edge servers. The specification uses a pair of 400-pin connectors (a total of 800 pins), which allows signalling rates up to 32GTps.
There are three module types:
* the client module fixed voltage input
* the client wide range input voltage
* the server module with a fixed input voltage.
The client module type serves applications with one or more displays and low to very high bandwidth. Examples are medical equipment, instrumentation, industrial equipment, gaming equipment, transportation and defence systems.
The server type is intended for embedded servers with no displays and which need a large CPU capability, large memory, high bandwidth I/O and up to 65 PCIe lanes. These are larger applications than the client module, such as autonomous vehicles, base stations and large pieces of medical equipment and defence systems.