Bluetooth and Wi-Fi capabilities are paramount for many tasks in the Internet of Things. Deploying a well-established wireless coprocessor simplifies hardware and software integration and can help with certification and driver development.

Raspberry Pi's microcontrollers and single-board computers are usually paired with a wireless module from Infineon. In the case of the SC0918, for example, a CYW43439 was used (and heavily modified) to provide both Bluetooth and WLAN support.

With the RM2, also known as RMC20452T or SC1169, the Raspberry Pi PLC now provides a ready-to-go wireless module based on the same chip. Its form factor allows for ESP32-like integration into host PCBs.

Direct Raspberry Pi Pico integration

Given that the RM2's core is used on both SC0918 and SC1633 development boards, adding the module to a new Raspberry Pi microcontroller design is accomplished via the schematics below. The gSPI interface handles data transmission, while additional power-control pins handle energy management. Interestingly, the module exposes a few of its own GPIO pins, compensating for the pins lost on RP2040 designs.

Designers seeking to integrate the module into non-Raspberry Pi-provided platforms are provided with the following warning in the datasheet. It is evidence of the extremely high quality of integration between the SDK and the wireless transceiver:

RM2 is designed to be paired with host software and a gSPI interface enabled via the programmable PIO cores present in all Raspberry Pi microcontrollers. Use of RM2 with non-Raspberry Pi microcontrollers is unsupported. This means that attempts to integrate RM2 with other platforms will likely fail due to incompatible interfaces, firmware dependencies, and a lack of required PIO-based gSPI support.

Wide Wireless Protocol Support

Based on the CYW43439, the Raspberry Pi wireless module supports WiFi 4 (standards 802.11b/g/n) and Bluetooth 5.2, along with the corresponding low-energy variant. Thanks to the integrated 2.4GHz antenna, the wireless module is ready to go after PCB integration -- no costly and time-consuming antenna matching with a vector network analyzer is required. However, designers should adhere to the RF keepout area as specified in the figure.

As for radio channels, the datasheet provides the following information:

Supports 20 MHz channels with data rates up to 96 Mbps (PHY rate).

As for power consumption, the official announcement of the module states the following:

IEEE Power Save PM1 DTIM1 average rate 1: 1.19 mA

Receive active rate MCS7 (at --50 dBm): 43 mA

Transmit active rate MCS7 (at 16 dBm): 271 mA

Conclusion

If a design in the Raspberry Pi ecosystem needs wireless functionality, deploying the SC1169 is a surefire bet. Thanks to the excellent software integration, most development environments intended for the RP2040 and RP2350 families support it out of the box. This leads to a significant reduction in the total cost of ownership and dramatically simplifies software development.