Raspberry Pi Pico 2, our new $5 microcontroller board, on sale now

Original Article ↗ Hacker News Discussion ↗

Overall Reception and Use Cases

  • Many are excited about the RP2350’s feature upgrades over RP2040: dual Cortex‑M33, dual RISC‑V cores, more RAM/flash options, extra GPIO, more PIO/DMA channels, secure boot, RNG, crypto accelerators, HSTX high‑speed serial.
  • Consensus that Pico 2 remains a microcontroller board, not a desktop; unsuited to tasks like running Firefox or Vim as a primary dev machine. Full Raspberry Pi boards (Pi 4/5/400) are suggested for that, though some find even those slow for web development.
  • PIO is highlighted as a major differentiator vs ESP32: programmable state machines offload tight‑timing I/O (VGA, PWM, custom protocols) from the CPU.

ARM + RISC‑V Dual Architecture

  • Strong interest in how two architectures coexist. Clarified that both ARM and RISC‑V cores are present in silicon, selectable per core at boot via a register.
  • Some surprise it didn’t increase die size measurably; explanation is that pad ring and layout constraints limited die shrink anyway.
  • Debate on practicality of running one ARM and one RISC‑V core concurrently; use cases seen as unclear.

Connectivity and Comparison to ESP32

  • Criticism that Pico 2 lacks onboard wireless and “isn’t competitive” with ESP32.
  • Counterpoints: many embedded uses don’t need radios; a wireless Pico 2 W is announced for later; RP-series PIO and 5V‑tolerant I/O provide different strengths.
  • Clarification that RP2040/RP2350 are MCUs; Pico W boards add a separate Wi‑Fi/BLE chip, unlike integrated ESP32.

USB, Power, and Battery Management

  • Frustration over continued micro‑USB instead of USB‑C; defenders cite drop‑in form‑factor compatibility and existing cable stock.
  • Technical discussion that proper USB‑C support needs CC resistors; cheap boards often omit them, causing C‑to‑C cable issues.
  • On‑board switching regulator still needs external inductor/passives; only the controller is on-chip.

Memory, Displays, and Peripherals

  • Enthusiasm that RP2350 supports external QSPI PSRAM with proper read/write mapping, unlike earlier “hacky” RAM extensions.
  • Explanation that higher‑resolution TFTs need substantial RAM/bandwidth (e.g., for framebuffers and double buffering).
  • HSTX block (8 high‑speed outputs) and higher PIO count viewed as useful for fast serial/video‑like interfaces.

Security and ADC Improvements

  • Secure boot, encrypted boot, dual security contexts, and RNG/crypto are seen as enabling low‑cost secure enclaves or simple HSM‑like devices.
  • ADC fixes remove known nonlinearity spikes; effective resolution is only slightly better (around +0.5 ENOB), which disappoints those hoping for a major ADC upgrade.

Environmental and “Board Hoarding” Discussion

  • Several reflect on accumulating unused boards and e‑waste.
  • One side argues personal Pi consumption is negligible vs larger impacts (kids, flying, cars); others say individual choices and reuse (donation, resale) still matter.
  • Suggestions include donating old boards to makerspaces or selling on the used market; concern raised that secure‑boot locking could limit reuse if irreversible (status unclear).

Documentation and Datasheet Quality

  • The RP2350 datasheet is widely praised as unusually clear, readable, and well‑structured, with good explanations of reset, power, and clocks.