11 Recommended Verification Procedure
After completing the design and manufacturing of a board or debugger using the Nano Debugger, it is important to verify the hardware. This step ensures that your design meets all specified requirements, rather than serving as a test of the individual hardware components. Hardware verification is typically performed once per board revision.
| Function | Check | Expected Results |
|---|---|---|
| Visual inspection | Examine all components for type and value, placement, and orientation where applicable | All components are mounted correctly |
| Measure for shorts | Impedance between VBUS and GND | In the range of 40 kΩ to 100 kΩ |
| Impedance between the 3.3V rail and GND | In the range of 100 kΩ to 250 kΩ | |
| Power supply | The LDO delivers a clean, stable supply | 3.3V measured using a calibrated tool |
| Overall power consumption | In the range of 10 mA to 20 mA | |
| MCU and USB | The Nano Debugger enumerates correctly on the host computer | The Device Manager (or equivalent) shows a Curiosity Virtual Serial Port |
| LED | The LED illuminates | The intensity is satisfactory |
| ADC paths | The VBUS voltage is read accurately | Matches a multimeter reading |
| The external voltage is read accurately | Matches a multimeter reading | |
| Target level shifters | Reset, clock and data lines work when using the Nano Debugger with a suitable target device | The device can be contacted |
| Repeat at various voltages | Equal results are observed across the expected operating range of the system | |
| CDC level shifters: | Transmission and reception using the CDC | Data can be sent and received |
| Repeat at various voltages | Equal results are observed across the expected operating range of the system |
Tip: The USB bus voltage and target voltage can be read using:
pymcuprog getusbvoltage
pymcuprog getvoltage