175 MB/s HDMI streaming from a $5 Pico 2

A Raspberry Pi Pico 2 can be turned into a high-speed data capture node that pushes up to 175 megabytes a second through an HDMI link into a cheap USB 3.0 capture stick. (github.com) The project is called hsdaoh-rp2350, short for high-speed data acquisition over HDMI, and its public repository says it runs on Raspberry Pi’s RP2350 chip with overclocking on a Pico 2 board. The same readme says the setup uses low-cost capture devices based on the MacroSilicon MS2130 chip as the receiver on the computer side. (github.com) In plain terms, the trick is to treat HDMI less like a display cable and more like a fast pipe for raw measurements. The Pico 2 fills a memory ring buffer with samples, then sends that stream out through the RP2350’s high-speed transmit block while a host computer reads it through a USB 3.0 video grabber. (github.com; raspberrypi.com) Raspberry Pi launched Pico 2 on August 8, 2024 at $5, built around the RP2350 microcontroller. Raspberry Pi says RP2350 adds a new high-speed transmit peripheral, twelve upgraded programmable input/output state machines, 520 kilobytes of on-chip static random-access memory, and dual 150 megahertz Arm Cortex-M33 cores. (raspberrypi.com; raspberrypi.com) That matters for hobby test gear because microcontrollers usually hit a wall when they need to move large amounts of live data off-board. The hsdaoh-rp2350 examples include a 16-channel logic analyzer, an internal analog-to-digital converter streamer, and an external 12-bit analog-to-digital converter path that can clock an AD9226 board at 40 megahertz by default and up to 96 megahertz with higher overclocking. (github.com) The project’s main repository places the Pico 2 version alongside earlier hsdaoh designs built around small field-programmable gate array boards, which are chips that can be rewired after manufacture for custom digital hardware jobs. That repository says the RP2350 version can reach 175 megabytes a second while the programmable input/output blocks provide the external interface for incoming signals. (github.com; github.com) The capture-stick side has caveats. The hsdaoh documentation says users need real USB 3.0 devices based on MacroSilicon MS2130, MS2131, MS2130S, or MS2131S chips, and warns that some cheaper sticks use older USB 2.0 hardware or mislabeled parts that will not deliver the same throughput. (github.com) The Pico 2 hardware itself is still a $5 board in Raspberry Pi’s current product listing, but the rest of the setup is not literally $5 because it also needs an HDMI breakout or socket arrangement and a compatible capture stick that the hsdaoh documentation says typically costs about $10. (raspberrypi.com; github.com) The immediate result is not a new display device but a cheap front end for measuring fast digital or analog signals on a PC. For people building software-defined radio receivers, video-signal capture tools, or homebrew logic analyzers, the appeal is that a board Raspberry Pi sells for $5 is now being used as the sender in a data path measured in hundreds of megabytes per second. (github.com; raspberrypi.com)