Extended family of Pi-based edge computing servers

Sfera Labs has extended its Strato Pi CM family of compact Raspberry Pi-based Compute Module (CM) servers with two new models offering support for the new Raspberry Pi Compute Module 4S alongside other performance improvements. The Strato Pi CM v3 and Strato Pi CM Duo v3 are ideal for industrial and IoT applications varying from energy management and data collection to constructing automation and control of marine systems.

The latest Strato Pi CM/CM Duo v3 versions offer users the benefits of the enhanced performance of CM4S, which is based on the CPU employed in the Raspberry Pi 4 Model B and is notably more powerful than the CM 3+ and the older CM 3, which are all supported for back compatibility. The new models provide enhanced protection of the RS-485 lines and a re-designed real-time-clock circuit with enhanced timekeeping accuracy and extended backup battery life. Each product keeps the same watchdog, isolated RS-485 port, and USB ports with independent power control and fault detection built into past generations of the devices.

The devices include two USB ports, which can be individually power-cycled, and circuit fault protection and detection are on each port. This offers the ability to turn off and back on an external USB-powered device under the module's control should the device become locked, therefore, avoiding long downtimes and costly on-site maintenance.

Strato Pi CM Duo offers two microSD card slots and an innovative high-speed switch matrix that enables the Raspberry Pi Compute Module to boot the operating system from SD card whilst at the same time offering full access to the other SD card for extra storage or to keep an up-to-date failover image of the operating system and data. This architecture allows a full-image upgrade of the Pi's operating system to be performed on one SD card while the system runs from the other. Following verification of the new image, the device can restart the Compute Module, booting from the second SD card. If the boot process is unsuccessful, it will safely roll back to the original SD card.

Furthermore, the device microcontroller's firmware can be upgraded remotely from the Pi. The Raspberry Pi remains fully functional during the upgrade, thanks to the pre-installed boot loader and our open-source utilities.

The devices include a Secure Element chip, enabling the storage of security keys and implementing other security features on a dedicated hardware device.