The Raspberry Pi Pico is becoming a Swiss Army knife of microcontrollers and this is largely due to the flexibility provided by the programmable IO (PIO) and the price of $ 4. In the latest a project to get our attention, we see Luigi Cruz, a computer student and amateur radio enthusiast, use Pico as a software-defined radio (SDR) interface for the popular GNR Radio application.
Cruz’s SDR project, PiccoloSDR, uses one of the analog input pins to sample 8 bits of data at 500ksps. Cruz has connected Pico’s analog input to the output of his sound card and uses an online tool to generate tones that are visible on his computer. To connect Pico to the computer, Cruz explains: “The data is sent via USB using the RNDIS protocol to emulate the TCP / IP interface. The ADC speed is limited to 500 ksps. The data can be used with software such as GNU Radio with custom This provides a low bandwidth tool for receiving data from Pico and in applications such as GNU Radio.
Cruz continues the demonstration, showing how you can use GNU Radio to view and analyze audio inputs; for example, Cruz plays a video file and we can see the audio frequency and sampling rate in GNU Radio.
It’s still early days for PiccoloSDR, but we can see a power supply with the Raspberry Pi Pico for basic electronics work. There is currently no public code with which to reproduce this project, but it is only a matter of time before Cruz announces the details through his Twitter account.