Cellular IoT gateway solution enables connectivity for industrial systems


TZero’s MachineMailbox employs Nordic’s nRF9160 SiP to provide LTE-M/NB-IoT connectivity for data transmission

Nordic Semiconductor today announces that TZero, a State College, PA-based technology company, has selected Nordic’s nRF9160 low power System-in-Package (SiP) with integrated LTE-M/NB-IoT modem and GPS to provide the wireless connectivity and processing power for its ‘MachineMailbox’ machine connectivity tool. The solution is ready out-of-the-box to help industrial customers with remote compliance, equipment diagnostics and maintenance, and process optimization. 

Industrial IoT solutions

MachineMailbox is a Nordic nRF9160 SiP-powered proprietary gateway solution designed to enable connectivity in critical systems where network access is challenging. It converts any product into a connected Industrial Internet of Things (IIoT) sensor/machine-based solution with “zero configuration”, the company claims. 

For example, the solution can be deployed to enable fermentation monitoring in a brewery environment where critical level and temperature data would previously have to be collected manually. Using MachineMailbox, sensors in the brewer’s tanks collect data that is relayed to the TZero gateway, and in turn to the Cloud using the LTE-M/NB-IoT cellular network enabled by the nRF9160 connectivity. The company favors cellular IoT connectivity over Wi-Fi, for example, because the industrial-grade service offering needs to provide reliable wireless connectivity to transfer sensor data to the Cloud with no digital security limitations and minimal local configuration complexity for the end user. 

For MachineMailbox the key hardware feature of Nordic’s nRF9160 SiP was the integration of the Arm Cortex-M33 application processor with the cellular modem in a single package
Eli Hughes, TZero Research and Development

MachineMailbox connects to external sensors via a wired data port, which allows for flexibility in the types of applications that can be serviced. Once MachineMailbox sends information to TZero’s internally developed backend Cloud platform (deployed on Microsoft Azure), applications can also be customized with additional processing, sensor fusion, notifications, and visualizations. MachineMailbox fully utilizes the nRF9160 SiP’s 64MHz Arm® Cortex®-M33 processor and 1MB Flash and 256kB RAM to manage and perform the complex proprietary algorithms demanded by multiple sensors, as well as ‘bridge’ the data from its data port to the cellular network. 

The nRF9160 SiP is certified for global cellular IoT applications, comprising a dedicated application processor and memory, multimode LTE-M/NB-IoT modem with integrated RF front end (RFFE), GPS, and power management in a compact 10 by 16 by 1mm package. The dedicated application processor handles firmware updates, local configuration, some data reduction, logging, and diagnostics for the MachineMailbox platform. 

Along with the processor and generous memory allocation, the SiP includes a range of analog and digital peripherals, automated power and clock management, Arm TrustZone® for trusted execution, and Arm CryptoCell™ 310 for application layer security. The processor communicates with the LTE modem through a BSD secure sockets API and supports the application layer protocol (for example CoAP, MQTT or LWM2M) and the application itself. The nRF9160 SiP’s LTE modem supports both SIM and eSIM, offers 700 to 2200MHz LTE band support, 23dBm output power, -108dBm RX sensitivity in LTE-M, and -114dBm RX sensitivity in NB-IoT mode, and single pin 50Ω antenna- and UICC-interfaces. The SiP supports both PSM and eDRX power saving modes. For both LTE-M and NB-IoT the PSM floor current is as low as 2.7µA, and with an eDRX interval of 655 seconds the average current is 6µA for LTE-M and 9µA for NB-IoT. With the modem switched off the current is 2.2µA. 

Related products include the nRF9160 DK, a precertified single board development kit and the nRF Connect SDK (Software Development Kit) which includes application layer protocols, application examples, and LTE modem firmware offered as precertified and precompiled downloads. Target application for the nRF9160 SiP are asset tracking, smart city, smart agriculture, industrial, wearables, and medical among others. 

nRF9160 plus Zephyr RTOS

“For MachineMailbox the key hardware feature of Nordic’s nRF9160 SiP was the integration of the Arm Cortex-M33 application processor with the cellular modem in a single package rather than [a separate processor] being coupled to an external modem,” says Eli Hughes, CTO of TZero Research and Development. 

“As much as possible we leveraged Nordic’s nRF Connect SDK based on Zephyr RTOS, which provided immediate benefits in the level of information we could access from the modem component compared to other solutions and accelerates our future projects. The nRF9160 SiP plus Zephyr RTOS combination provides a good balance between simple application development and access to lower-level facilities. Plus, Nordic sets the standard for providing documentation and reference designs.”