iLabs' Challenger+ RP2350 NB-IoT Puts Low-Power Long-Range IoT Connectivity on Any Breadboard

Hobbyist electronics specialist iLabs has launched a new entry in its Challenger family of microcontroller development boards, this time combining a Raspberry Pi RP2350 two-of-four-core heterogeneous microcontroller with an STMicroelectronics Narrowband-Internet of Things (NB-IoT) radio: the Challenger+ RP2350 NB-IoT.

"The Challenger+ RP2350 NB-IoT pairs the powerful Raspberry Pi RP2350 dual-core microcontroller with the certified ST87M01-1301 NB-IoT module from STMicroelectronics," iLabs' Pontus Oldberg says of the new board, "giving you global low-power cellular connectivity, integrated GNSS [Global Navigation Satellite System] positioning, and the full Challenger/Feather ecosystem in a single compact board. It charges a LiPo [Lithium-Polymer] battery over USB [Type]-C, runs Arduino, MicroPython, and CircuitPython, and fits on a standard breadboard."

The Challenger+ RP2350 NB-IoT, brought to our attention by Linux Gizmos, is designed to fit into the Challenger ecosystem, which is in turn compatible with the popular Feather gumstick-format breadboard-friendly development board standard. The board is built around Raspberry Pi's second-generation in-house two-of-four-core microcontroller, giving it the user's choice of any two from a pair of proprietary Arm Cortex-M33 or open-hardware Hazard3 RISC-V cores running at up to 150MHz, 520kB of on-chip static RAM (SRAM), and 8MB of off-chip flash, plus a Programmable Input/Output (PIO) block supporting up to 12 state machines.

Connected to this is an STMicro ST87M01-1301 NB-IoT module, supporting Cat. NB2 3GPP Release 15 on bands B1, B3, B5, B8, B20, and B28, offering up to 159kb/s and 127kb/s uplink and downlink throughput respectively. The module also includes the ability to scan for nearby 2.4GHz 802.11b-compatible wireless access points in order to provide indoor positioning, and includes a GNSS receiver with GPS L1 and Galileo concurrent-mode operation with assisted GNSS (A-GNSS) operation via ephemeris data downloaded over the NB-IoT connection.

Elsewhere on the board is a USB Type-C connector for power and data with support for charging an optional lithium-polymer battery, either via USB Type-C or the board's VUSB pin. General-purpose input/output (GPIO) connectivity is brought out to 0.1" pin headers on the boards' long edges, and includes access to SPI, I2C, and UART buses, analog-to-digital and digital-to-analog (ADC/DAC) conversion, and pulse-width modulation (PWM) support. There's a nano-SIM slot for the NB-IoT connection, with an "evaluation only" card supplied in the box.

The Challenger+ RP2350 NB-IoT is now available to order on the iLabs store at SEK549 (around $58).