Hardware-in-the-Loop: Closed-loop Validation Online, EMI Is Next
New PCB passes everything: ESP32-S3 boots and USB-CDC communicates; the I2C bus mounts PCF8574AT (key extension) and INA219 (current sensing), both responding accurately; 4-channel digital inputs and GPIO (relay/LED) logic verified.
The loop framework achieved real “Hardware DevOps”: fixed the macOS USB-CDC serial lock on ESP32-S3 so flashing is fully automated; validated --firmware-dir cross-project sequential runs; and it now auto-generates test audit packages to seed small-batch production.
Next battlefield: motor-control experiments showed motor operation interfering with comms. Next up — decoupling high-frequency motor noise from communication stability.
“Make hardware development as testable and reproducible as software. By solving serial-port locks and EMI, we are one centimeter closer to ‘Design as Manufacturing’.”