I made a 10 Cent MCU Talk I taught a 10¢ CH32V003 RISC‑V MCU to talk. By bit-banging PWM as a DAC and using a tiny 2‑bit ADPCM decoder, I squeezed ~6–7 seconds of recognizable audio into 16 KB of flash. Then I went full retro with LPC speech synthesis (Think: Speak & Spell) using the Talkie library and a small web tool I built to generate LPC data—so this little 8‑pin chip can now play samples and ‘speak’ lots of words with only a few kilobytes. 29 October 2025
Brain Surgery I cracked open a cheap Halloween toy, found the super-simple LED + LR41 setup with the arm-as-switch trick, and swapped the ‘empty head’ for my own CH32V003 + buzzer PCB. Now it screams as well as shines—powered by a small lithium cell for extra volume because if you’re going to be annoying, do it properly. New schematic, new brains, same spooky vibes. 24 October 2025
10 Cent Music Machine I built a tiny coin‑cell music board around the $0.10 WCH CH32V003J4M6 (8‑pin, 48MHz RISC‑V, 16K flash/2K RAM). The PCB is just 16.3×11.7mm with a piezo buzzer and transistor, and in standby it sips 7–8µA. I did hit a snag: playback caused 130mA peaks that browned out a CR2032. A LiPo fixed it, but I really wanted coin‑cell, so I upped the buzzer’s base resistor to 10k, dropping peaks to 56mA and average to ~7mA—now it runs happily (and loudly) from a coin cell. Pro tip: if standby bricks programming, wlink can erase via power-off mode. I’m bit‑banging audio, published... 12 October 2025