Skip to content

Introducing Interface MCU

Introduction

The nRF9151 Connect Kit comes with an on-board Interface MCU built using the nRF52820. The Interface MCU Firmware is running on the nRF52820. It implements a CMSIS-DAP interface for debugging and programming the nRF9151 SiP. It also exposes two USB CDC ACM devices, one acts as a UART bridge between the host and the nRF9151 SiP, the other enables an Interface Shell for accessing board-specific functionality such as battery charger settings.

The Interface MCU also comes pre-programmed with the UF2 Bootloader, an easy-to-use and self-upgradable bootloader that can be used to update the firmware by just copying the .uf2-format images to the flash drive without using an external programmer.

The following figure describes the functional architecture of the Interface MCU:

Why Choose the nRF52820

The nRF52820, with its rich feature set and low-power design, is an excellent choice for implementing an Interface MCU.

  • Low Power Consumption: Ultra-low power is in Nordic's DNA. The nRF52820 draws less than 1 µA in System OFF mode, making it an ideal choice for battery-powered applications.
  • High Performance: The nRF52820 features a 64 MHz Arm Cortex-M4 processor with 256 KB Flash and 32 KB RAM.
  • Full Speed USB 2.0: The nRF52820 integrates a USB 2.0 full speed (12 Mbps) controller, which allows the SoC to support multiple functions, such as HID and CDC, simultaneously.
  • Cost-Effective: The nRF52820 integrates many features into a single chip, reducing the need for additional external components. This integration lowers the overall Bill of Materials (BOM).
  • Comprehensive Development Ecosystem: Compatible with Nordic’s nRF Connect SDK. This makes it easier to develop and debug applications.

Getting Started with the Interface MCU

The Interface MCU firmware is open source, and detailed documentation is available to help you get started.