A USB power meter squeezed into 16 KB of Flash: voltage, current and power readout up to 20 V / 5 A, PD 2.0 pass-through, energy statistics, and a power-history curve on a 0.96-inch OLED — all driven by the 10-cent RISC-V MCU.
| Platform | GitHub / OSRTOS |
|---|---|
| Author | Community project (see project page) |
| License | Open source (see project page) |
| Silicon | WCH CH32V003F4U6 + INA219 |
| What it is | A pass-through USB meter built around the CH32V003F4U6 and a Texas Instruments INA219 current monitor. The PCB uses wide 8 mm traces for the 100 W current path. |
|---|---|
| Why it is interesting | A case study in resource-constrained firmware: I2C driving the INA219 and the SSD1306 OLED on one bus, internal-Flash EEPROM emulation for cumulative energy, and binary-size optimisation to fit the 16 KB budget. |
| Tooling | Built with the noneos-sdk on PlatformIO, flashed with a WCH-LinkE on SWDIO/NRST. Gerbers, BOM and 3D-printable enclosure files are part of the release. |
| For you | A complete, manufacturable design to study if you want a shipping-quality reference for CH32V003 products with a display and analog front-end. |
Where is the repository?
The OSRTOS project page links the full source, PCB files and enclosure STLs.